Friday, May 8, 2015

Climate change: How we know it is real and what we can do about it

As the 2016 presidential election becomes harder to ignore, I realized to my surprise that so far I have been silent on an issue that is incredibly important to me and much more controversial than it should be. The time has come for me to firmly plant my flag concerning the reality of climate change.

The fact of the matter is that the Earth is warming at an unprecedented rate, most of this warming is due to human activity, it is already having an increasingly negative effect on biodiversity and our ability to thrive, and it will have catastrophic consequences if we do not take action soon to reduce our production of greenhouse gases.

The science

The scientific basis for global warming is well-understood, based on physical principles that are beyond questioning, and supported by observation. The greenhouse effect, the process by which atmospheric gases (primarily water vapor and carbon dioxide, but also methane and others) absorb and trap heat radiated by the earth, is entirely uncontroversial, supported by basic science and observation of the Earth as well as other worlds (especially Venus, where it is responsible for the lead-melting temperatures). Thus, as the concentrations of "greenhouse gases" in the atmosphere increases, we should expect them to retain more heat, producing a net atmospheric warming effect.

And this is exactly what we observe. Recent measurements show that the concentration of carbon dioxide in the atmosphere is steadily increasing. (The red line is the raw measurements, the black line is after correction for seasonal variation)
Over a somewhat longer timescale, we see that it might actually be exponentially increasing.
Lately, the growth rate of CO2 concentration has been about 2 ppm (parts per million) per year, or about 15 billion tons per year.
There is abundant evidence that this change in atmospheric carbon is anthropogenic (manmade). Human emissions of CO2 per year (see page 45 of that publication) are about 30 billion tons per year. This means that rather than producing a net emission of CO2, nature is in fact absorbing about half of the CO2 we emit. Additionally, atmospheric oxygen levels are steadily decreasing, which is just what we'd expect if the excess CO2 is being produced by burning carbon (i.e. fossil fuels) rather than by being released from a natural reservoir.
Over a longer timescale, this plot shows the correlation between the current rise in atmospheric carbon and human industrialization, beginning in the 19th century. By far the most obvious conclusion is that atmospheric carbon levels are increasing because we're putting it there by the burning of carbon-based energy sources.
One more plot shows the range of natural variation of atmospheric CO2 levels over a much longer timescale, and the relative magnitude and suddenness of the recent increase. Yes, carbon levels have changed in the past, but the present increase is virtually unprecedented in both its size and rapidness—150 years is the blink of an eye in geologic terms, and in that time we have already matched the increase in carbon over the past 11,000 years since the last ice age. Recently, atmospheric carbon reached 400 ppm—its highest level in the last three million years.
If the greenhouse effect works, this increase in atmospheric carbon should produce an increase in global temperatures. And it does. This plot shows five independent data sets of global surface or lower atmosphere temperature over the past 35 years. The second, smoother graph shows the data after removing the effects of the El Niño Southern Oscillation, solar variability, and volcanic emissions (several of the common natural explanations given for global warming). After filtering out these natural variables, a clear trend toward warmer temperatures remains.
This change in observed global temperatures can be correlated with a number of other variables, some of the most obvious of which are depicted below: receding glaciers and ice caps, rising sea levels and temperatures, changes in the migration and habitation of plant and animal species, and increasing humidity. Independently measuring and correlating all of these indicators considerably strengthens the case for a warming planet. And besides scientific measurements, the effects of global warming are already being felt around the world: increased flooding in coastal cities, record-breakingly hot months/summers/years/decades, and (in the past few years) the devastating drought in California. The effects of climate change are felt perhaps nowhere as strongly as in Pacific island nations like Tuvalu, the Marshall Islands, and the Maldives whose very existence is threatened by rising sea levels.
Again, this warming trend can be traced back to the previously mentioned manmade increase in atmospheric carbon levels by a variety of means. The independence with which these indicators can be measured and correlated with each other makes the case for anthropogenic climate change much stronger than it would be if it were based on only one variable.

The danger

You may be asking, "so what?" Carbon levels and global temperatures have fluctuated widely in the past (as previously mentioned, our current level of atmospheric carbon was last reached 3 million years ago), so how do we know that the era of global warming will actually be worse rather than just different? Well, as also previously mentioned, the difference between manmade climate change and natural climate change is one of both scale and rate. An optimistic estimate of 2° C of warming will push global surface temperatures to a level not seen since the last time we had this much carbon in the atmosphere, the Pliocene era three million years ago. And if we keep producing carbon at anything like our current rate, this number will likely be higher. Most species alive today didn't even exist tens of millions of years ago when things were last this hot, so we can't expect them to be able to adapt.

Even more significant is the fact that while climate changes naturally over the course of thousands or tens of thousands of years (during which greenhouse gas emission and absorption remain roughly balanced at all times), manmade climate change is operative over just a few hundred years—orders of magnitude faster than the natural rate. Past instances in which atmospheric carbon levels and global temperatures changed suddenly and in an imbalanced way (as they are doing today), due to large igneous provinces or other causes, almost always resulted in mass extinction events—and it is very likely that our actions are sending the Earth into another one, as they are producing the same symptoms by the same means. The stress we have placed on species and ecosystems through other means like pollution, habitat loss, overhunting/fishing, and the introduction of invasive species makes it even harder for them to adapt to manmade climate change as they have to natural climate shifts in the past. This article explains these difficulties in more depth.

While warming temperatures may bring some positive effects, like improved agriculture and vegetation activity at higher latitudes and an ice-free Northwest Passage, the negative effects are expected to be far greater. These include unhappy things like decreased water supply and desertification (as in California), increased danger of heat stress, the growth of oxygen-poor zones in the ocean, extinction of numerous vulnerable species and the loss of biodiversity, and the displacement of hundreds of millions due to sea level rise. All of these things will carry catastrophic economic consequences for developing and developed nations alike. Still more troubling are effects like decline in global phytoplankton and the leakage of methane from formerly frozen areas that will create positive feedback, further intensifying the warming of our planet. In theory, if the planet warms enough to push the water vapor concentration in the atmosphere to a sufficient level, the feedback could become into a self-sustaining loop that would turn the Earth into a second Venus (though we would likely already be doomed well before it got to this point).

The consensus

The scientific consensus on climate change is clear and unequivocal. A survey of peer-reviewed climate science papers found that 97% of the papers expressing a position explicitly affirm that anthropogenic climate change is real. If this figure seems surprisingly low, keep in mind that the 3% includes implicit (rather than explicit) endorsements, implicit rejections, and no opinions. Another, similar survey which only counted explicit rejections of anthropogenic climate change found that 24 out of 13,950 articles reject global warming—just 0.17%. This consensus is even stronger (at least 98% explicitly affirming) in more recent papers.

In light of all this, it saddens me to see so many of our nation's leaders (and the people who voted for them) willfully ignore the scientific consensus in favor of their own fantasies about climate change: that it is not happening, that is it is not a problem, that it is not caused by us, that there is no consensus, or that there is no need for them to take action because "I'm not a scientist" (and, apparently, not willing to trust them either). Certainly the media, in its well-intentioned dedication to balance, is partly responsible for enabling this ignorance: it creates the illusion that climate change is a two-sided issue under discussion rather than a matter of scientific fact. But really there is no "debate" or "conversation" regarding the reality of climate change; there is only an overwhelming consensus and those who (all too often for political or ideological reasons) refuse to accept it.

As an analogy, consider the fact that due to tidal acceleration, the Moon is moving away from the Earth at a rate of about 3.8 cm/year. This trend is not immediately or intuitively obvious to an observer, but it is well explained by basic physical principles and verifiable by multiple methods: studying ancient observations of eclipses to establish the Moon's position in the past, gravitational data from satellite laser ranging, and simply bouncing light pulses off the retroreflectors left by the Apollo astronauts and measuring the return delay. Scientists are just as certain that anthropogenic climate change is happening as they are that the Moon is drifting away from the Earth. I have never heard anyone express doubt about the latter. Why is the former any different—because of its implications for how we live? Our own desires, interests, and preferences cannot change the truth of what we are doing to the climate.

The theology

My knowledge of the fragility and beauty of the Earth and our dependence on it, as well as my own experiences in nature, would be sufficient to instill in me a deep and abiding concern for environmental issues, especially anthropogenic global warming, dangerous as it is. But as a Christian, I have another, even stronger foundation for environmental concern and action.

In Genesis 1 God creates the heavens and the Earth (v. 1) and all the life on the Earth, declaring everything that he had made "very good" (v. 31). He also creates mankind in his image, to fill the Earth and subdue it and have dominion over nature. (v. 28) Does this mandate give us license to do as we please with the environment? No, for it must be considered along with the innate goodness of created nature and our role as God-appointed regents over it. If the creation is really good, and not "fallen"/evil or simply morally neutral raw material for our own designs, then by harming it we are harming God's handiwork. The image of God in man is not the only reason for human worth and dignity; simply being created at all conveys great worth and value. The mandate uses militaristic language ("subdue", "have dominion over") because of the present, frustrated state of the creation (cf. Rom 8:19-23), but this dominion always has as its intent wise, beneficent rule and redemption as God himself works, never exploitation or destruction.

The Psalms contain abundant examples of the value of creation as it reveals the glory of God. In Psalm 19 "the heavens are telling the glory of God" to the ends of the earth and the sun "like a strong man runs its course with joy". Psalm 33 praises God (through the Psalmist's ancient understanding of the cosmos) as the creator and ruler of the heavens, the earth, and the sea. Psalm 104 goes into considerably more detail, poetically describing the act of creation as well as God's ongoing governance of the created order, providing food for man and the animals; even the cycle of life and death is the occasion for praise. Psalms like these express what I have heard described as a sacramental view of nature which Fr. Stephen Freeman describes as the opposite of modern secularism, the reckoning of all the workings of the cosmos as a ceaseless act and a voiceless hymn of worship to their maker.

As an Orthodox Christian-to-be, I am happy to be part of a church which faithfully preserves and teaches this understanding of the cosmos. It is truly the basis for robust, authentic Christian environmentalism. As proof of this, one need look no further than the current ecumenical patriarch, Bartholomew. Like Pope Francis, he is deeply concerned about the human impact on the environment; unlike Pope Francis, he has already published a strongly-worded and very wise encyclical which expresses a theological basis for caring for the creation much better than I can (and takes a strong stance on climate change, much like the one the Vatican is expected to take). Even if you haven't been reading all the links I've been posting thus far, take just a few minutes and read it

One other way Christian teaching can contribute to the conversation on climate change is in its abiding concern for the poor. It is an unhappy fact of global warming that the nations most affected by it tend to be poor and developing (as well as very low in carbon emissions), while the nations least affected are predominately the wealthy nations responsible for causing it in the first place. It is a textbook negative externality on a global scale, a terrible injustice. Prominent among the Christian's reasons for environmental concern should be the awareness of the possible unjust effects of his/her actions on the poor who stand to lose the most to climate change—their crops, their livelihoods, even their homes and their lives.

In light of all this, arguments fielded by Christians in opposition to environmentalism are revealed for the falsehoods they are. Since they seem to exist solely among laypeople and not among scientists or theologians, I will not attempt to state them in a clearer, better-supported form as I usually do. These are not carefully-considered theological responses with any kind of historical pedigree or arrived at after careful reflection; they are from-the-hip answers that use Christian-esque ideas to justify a false position arrived at due to other factors.

First, I have heard it argued that God, as creator, is sovereign over nature, and that man doesn't have the power to change it or thwart his plans. My first response is that this is simply factually false. Man evidently does have the power to cause global-scale environmental changes because we are doing so and have already done so. This is simply undeniable, supported by reliable, repeatable observations; for instance, as shown above, we have demonstrably increased the carbon concentration of the atmosphere by about a third. Theological arguments can't falsify a scientific theory; only a scientific argument can. As Mark Noll explains in relation to young-Earth creationism in his book The Scandal of the Evangelical Mind, authentic Christian thinking requires listening to both "books" of God's revelation: Scripture and creation, not using your interpretation of one to contradict what we can know through the other. To do so is, ironically, to deny God as creator in order to confess him as sustainer of the creation.

Further, we know that God created us in his image as free, responsible beings with real moral agency and the ability to make real moral choices. This is implicit in all of the Bible's ethical commands, which wouldn't make sense otherwise, and has always been the teaching of the Orthodox Church. Sidestepping discussions of the exact nature or extent of this freedom, God's sovereignty obviously doesn't mean that he defends the integrity of his image in man by intervening to stop us from wronging or killing each other. Why then should we expect him to prevent us from sinning against the environment? There is no biblical support for such an idea, and plenty for the kind of Christian environmental ethic I sought to lay out above.

Additionally, this argument sidesteps the question of whether and how Christians are to care for the environment; it simply claims (without serious justification) that God will somehow restrain or prevent the negative consequences of our failing to do so, so there is no need to try. But if we really are appointed as stewards and even priests of the rest of the creation, then this argument is saying in effect that we should simply ignore this vocation because there was really no reason for God to give it to us in the first place. This is horribly irresponsible and dualistic, not to mention hubristic. "But who are you, O man, to talk back to God?" (Rom 9:20) By contrast, it is not hubristic at all to believe, on the basis of multiple independently measurable indicators, the sobering truth that human activity is having a major effect on the Earth's climate, which we have a mandate to care for. Rather, it is the beginning of humility and repentance.

The other argument I sometimes hear is similar to the first, but even worse. It is the sentiment that because Jesus is coming back to bring the old creation to an end and inaugurate the new, we don't have to be especially concerned about the environment. Similar to the previous argument, it basically states that we don't need to care about the effects of human activity on the environment because God will intervene to prevent them, in this case by returning to bring about the end of the world. In other words, it presumes that Jesus will return before climate change can begin to have catastrophic effects on future generations. But, in Jesus' own words, "watch therefore, for you know neither the day nor the hour." (Mat 25:13) Jesus was clear about few things relating to his return, but he was crystal clear about the fact that we can't know when it will be. (See also Mat 24:36,44,50; Mar 13:32; Luk 12:40,46; Acts 1:7) Like the first argument, it sidesteps any kind of teleological discussion of our appointed role as stewards of the creation, focusing only on why we will supposedly be spared from the consequences of scorning our calling.

Why not justify other corporate sins in this way? Why not support slavery, since Jesus will come back to break every chain? Why not selfishly exacerbate the suffering and poverty of people in developing countries (which, incidentally, is one of the effects of global warming), since Jesus will return to wipe every tear from their eyes? "And why not do evil that good may come?" (Rom 3:8) The return of Jesus and the last judgment, far from a cosmic reset button undoing our sins, will be a day of reckoning in which we will be called to account for all that we have done (Mat 25:31-46, Rom 2:6-8, 14:12, 2 Tim 4:1, 1 Pe 4:5, Rev 20:12). It is hard to imagine a greater folly than expecting the day in which everyone will be judged for what he has done to be the occasion for our escape from accountability for sins against the environment.

Edit: The sovereignty of God, invoked in the first counterargument, is relevant to discussions of the climate in another way. The Christian faith involves an unstoppable hope, based on the Incarnation, crucifixion, and resurrection of our Lord, that is sufficient to overcome even the grim certainty of death. Paul, describing this hope, says powerfully, "I am sure that neither death, nor life, nor angels, nor principalities, nor things present, nor things to come, nor powers, nor height, nor depth, nor anything else in all creation, will be able to separate us from the love of God in Christ Jesus our Lord." (Rom 8:38-39) So one implication of the sovereignty of God is that we are to remain hopeful and not despair no matter how bad things seem, since for many Christians they have seemed much worse. But not to fear is not to do nothing. Like any other issue incumbent on the Church, climate change demands a response, but that response should be out of hope, not fear or gloom.

What can we do?

In the face of these terrifying visions, and the continued politicized denial of climate change, especially by Republican leaders, it is very tempting (certainly for me) to simply despair of hope that anything can be done. At times like this it's very beneficial to rest and remind myself of some of the reasons for hope that we can actually address the climate crisis. But if you grasp the magnitude of the problem and the need for broad and deep action to address it, then remaining a bystander stops looking like a suitable option. I will try to present ways I have found to take personal action against climate change. Most of them are not that hard!

First, you can reduce your carbon footprint. Your carbon footprint is the sum of the carbon emissions caused by your actions and lifestyle, both directly (i.e. by driving or burning other fuels) and indirectly (e.g. by buying or using products that require carbon to produce or transport). Some ways to do this include:
  • Use less heating and air conditioning in your home. If you are a homeowner, this might mean insulting your home better to avoid having to heat it as much or installing a "smart" thermostat that only regulates your home's temperature when people need it. If, like me, you rent an apartment, you can still leave your thermostat at a lower temperature in winter and rely more on fans and opening/shading windows than air conditioning in the summer.
  • Minimize your energy usage. Ways to do this include using compact fluorescent bulbs for lighting (or, better yet, long-lasting and super-efficient LED bulbs), turning off lights when you leave a room, turning your computer off when not using it, and plugging devices that use power even when turned off (e.g. lots of electronics) into a power strip so you can fully de-power them when not using them. As previously mentioned, minimizing your use of heating and air conditioning also helps with this. If you are a homeowner, you can also try to install energy-efficient (e.g. Energy Star) appliances.
  • Use less hot water; heating water takes a lot of energy. If possible, you can do this by installing more efficient shower heads/faucets/toilets. Homeowners can also turn their hot water temperature down and/or ensure that their water heater is well-insulated.
  • The classic trifecta: reduce, reuse, recycle. This boils down to consuming and throwing away as little as possible. If you're unsure about what you can recycle, your city's web site should tell you. (Here is the one for Minneapolis as an example)
  • Drive less or not at all. When possible, use alternate forms of transportation like walking, cycling, carpooling, or public transportation. This may not be easy, but besides the environmental benefits it will also save you money, especially if you are able to completely replace owning a car with other ways of getting around. I am almost through my third post-college year without a car and loving it. I spend $85 a month on my bus pass and a total of about $200 a year on parts and maintenance for my bike. Not only do I save a lot of money, I love not having to spend lots of time driving or (as is all too often the case) sitting in traffic. Once we are married, my fiancee Marissa and I plan to own one car between us, which should be more than sufficient for our needs. This option may require some bigger lifestyle modifications, but can be quite worth it and have a major impact on your carbon footprint.
  • Eat less meat, especially red meat. Producing a given amount of calories of meat uses a lot more resources than producing the same amount of calories of plants. Even if you don't go fully vegetarian, reducing the amount of meat in your diet can make a sizable difference. Apparently minimizing your consumption of rice is also beneficial, since most rice is grown in methane-emitting paddies. Eating locally-grown food is also an obvious step (reducing fuel costs of transporting it), as is avoiding wasting food.
Second, you can offset your carbon footprint. This means supporting environmental projects that remove an amount of carbon from the atmosphere equal to the amount you put in. The cost of this is apparently just $15 per metric ton. The average carbon footprint of an American is 27 tons per year, which translates to an offset of $405, or just $33.75 per month. This is a surprisingly low price to pay to become "carbon neutral", and of course you can decrease it by lowering your footprint. This handy site lets you estimate your carbon footprint and donate to offset it.

And third, you can take action beyond your individual/household's carbon footprint. You can support organizations that are helping to fight climate change and promote the welfare of the environment like The Nature Conservancy, the Environmental Defense Fund, or the World Resources Institute. (The very useful website Charity Navigator can help you find another organization to support if you like) Or you can join the public conversation addressing climate change by signing petitions, writing to your elected officials about your concerns, or simply by telling others about it to raise awareness, perhaps by sharing concise, persuasive resources on the web (hint hint). The strategy and tactics of dealing with global warming are much more complex subjects than the basic scientific facts. Once we are in agreement that anthropogenic climate change is real, there is plenty of room for diversity of opinion on what to do about it, how to balance short-term needs and economic realities with the long-term need not to cook the planet to death. My goal in shutting down climate change denial is not to end constructive conversation, but to make it possible and invite more people into it by showing the obscurantist, anti-science rhetoric of denial for what it is and calling us to rise above it. If we are to resolve the climate crisis, we need all the voices—and hands—we can get.

Saturday, April 18, 2015

What If?

When I got my copy of Randall Munroe's (of the amazing webcomic xkcd) new book What If?I had been holding out hope that in it he would finally answer some of the (multiple) questions I've asked him. Unfortunately, he didn't (although he did answer a very similar one from someone else). So I guess the only thing left for me to do is to take a crack at answering them myself. Obviously, I am not a webcomic artist or an astrophysicist who used to work at NASA, so my answers won't be nearly as funny, well-illustrated, or (possibly) correct as Randall's would be. But hopefully they'll still be worth it. Let's go back through my old Emails...

If people packed shoulder-to-shoulder on every floor of a tall building and jumped, would they have any chance of bringing the building down?

Great question, me! As our example skyscraper, I'll use the shiny new One World Trade Center; since it was built to survive being hit by a hijacked airplane or a truck bomb, it should have at least as much of a chance as any other skyscraper.

According to Wikipedia, the "Freedom Tower" has 86 usable floors. The base is a 200-foot square footprint whose edges get chamfered as they rise up the building's side, ending in a smaller square rotated 45 degrees that fits in the first. The bottom floor (above the base) has an area of 40,000 ft² and the top has an area of half that, 20,000 ft². Let's assume that the average usable floor is 30,000 ft² ≈ 2,755 m². Let's further assume that 95% of that area can be stood on (i.e. is not a wall, elevator shaft, etc.), or 2617 m². If we assume three people can fit in a square meter, that's 7851 people per floor, or 675206 people total (nevermind the hellish logistics of getting them all in there, which would be almost as bad as Randall explains in his similar answer here).

If I then assume that an average adult weighs 75 kg and can jump 0.3 meters in the air (per this article), they would be traveling at v = √(2gh) = √(2 * 9.8 * 0.3) = 2.42 m/s when they came down. The force exerted by an impact is the change in momentum divided by time. How much time does it take for you to stop moving after you hit the ground while jumping? It's hard to find good figures, but from this solid-looking question from a physics textbook and some testing that would no doubt confuse my roommate if he saw it, I'm going to be conservative and say about 0.1 seconds if you're smart and bend your knees.

So, the force exerted by a 75kg person when landing from a jump is about 2.42 * 75 / 0.1 = 1,815 N, decelerating the person at about 2.5 g. The force from all 675,206 people would then be about 1.225 GN (giganewtons), the equivalent of about 125,000 metric tons. All of this force will be transmitted to the Freedom Tower's base. Will it survive? Well, considering how each of the old towers weighed about 500,000 tons (I can't find data on the new one), it's safe to say that this additional load should be well within the structure's margin of safety. That [architect of One World Trade Center] David Childs really thought of everything.

I hope it isn't in bad taste that I originally answered this question on September 11th.

What would happen if you somehow brought a cubic meter of neutron star matter to earth? (Both the actual case where it would probably explosively decompress, and the hypothetical case where it stayed together in a solid unit)

Randall almost answered this one in his new book. The actual question was, "If a bullet with the density of a neutron star were fired from a handgun (ignoring the how) at the Earth's surface, would the Earth be destroyed?"

My guess of what would actually happen was right. It would indeed explosively decompress into superhot normal matter, apparently releasing more energy than a nuclear bomb. So Randall assumes it somehow stays in its superdense state; the bullet would weigh as much as the Empire State Building.

It wouldn't matter much if the bullet were fired or dropped. It would immediately burrow its weight to the center of the earth, forming an underground shooting star, and would then sit there pretty uneventfully. He then explores what would happen if you could somehow keep it on the earth's surface. (Answer: if you tried to touch it, it would try to rip your arm off with gravity; surrounding it with water would allow buoyancy to cancel out the gravity and maybe, just maybe, allow you to touch it) It was a pretty cool question. But my question was about considerably more neutron star material. Let's see what happens...

According to Wikipedia, neutron stars have an average density of 3.7–5.9 × 1017 kg/m3. So our cubic meter of neutron star matter would weight about three to six hundred million billion kilograms. The Empire State Building weighs 365,000 imperial tons, or about 332,000 metric tons. So (if we take a middling estimate of the neutron star matter's density, 4.5 × 1017 kg/m3), our sample would have the mass of about 1.2 billion Empire State Buildings. Incidentally, it appears that Randall was (gasp!) wrong in his answer about the mass of the bullet. Assuming its volume is a teaspoon, it would weigh about as much as 7,410 Empire State Buildings, not just one. Sadly, this means you probably wouldn't be able to get within about twenty meters of it.

Anyway, our sphere (I'll assume it forms a sphere as expected rather than a cube) of neutron star matter is much bigger and much more massive. This means that its gravity becomes much more appreciable. The results are hard for me to imagine. The surface of the sphere will have a gravitation acceleration of nearly eight million g—four times that of the best ultracentrifuges. At ten meters, the sphere's gravitational force would still be equal to about thirty thousand g. This decreases to (only) 306 at 100 meters and 3 g at a kilometer. An easier measure might be that due to its smaller mass and radius, our neutron sphere has an escape velocity of 9.8 km/s, nearly equal to that of the earth. This also means that at six kilometers out, the gravity of the sphere would make you feel like you were on a slope with a grade of about 1:11.75—steep enough to constitute a violation of the Americans with Disabilities Act.

If you somehow kept this sphere together, it would, of course, fall to the center of the earth, probably causing a good deal more damage on the surface as it did so. If you managed to keep it on the surface as well, things would get pretty weird. If we assume the ground around the sphere is made of reasonably firm dirt with an angle of repose of 45°, all the dirt within about 1.7 kilometers of the sphere (along with anything on top of it) would avalanche towards it. As it turns out, because of the inverse-square law, an object just five meters from the sphere (the equivalent of dropping something to earth from beyond geostationary orbit) will, ignoring air resistance, have picked up 95% of its escape velocity when it impacts. It's hard for me to specify exactly what would happen, but the energy created by the hypersonic impact would probably be contained by the continuing avalanche of dirt, eventually resulting in a large, hot hill developing around the sphere. It puts me in mind of a certain song by Megadeth: "High Speed Dirt".

What would the atmospheric pressure be at the bottom of the Mariana Trench if you took out all the water?

This is much easier than the last question. The relationship between atmospheric pressure and altitude is common knowledge. The side effects of draining the world's oceans (which Randall studies exhaustively in the book) would slightly change things since there would no longer be oceans to displace the atmosphere upward, but this won't significantly change our results (I think). Plugging in the depth of Mariana Trench gives us a pressure of 3.65 atmospheres at the bottom. Apparently, if you stayed in this pressure for several hours, you could develop pulmonary oxygen toxicity, whose main symptom is respiratory inflammation. We all know that humans need supplementary oxygen to survive at high altitudes, but apparently exceedingly low altitudes have problems of their own.

The more interesting part has to do with the atmospheric lapse rate, or how quickly it gets colder as you go higher. It is about 6.5 K per kilometer. As you might guess, it also works in reverse. With the Mariana Trench being 10.911 kilometers deep, the air at the bottom should be about 70(!) degrees Celsius hotter than at sea level—potentially hot enough to spontaneously boil water, if water didn't boil at 140° C due to the increased pressure. Also, due to the Mariana Trench being over five times the depth of the Grand Canyon, it's hard to predict what kind of climatic effects will moderate this temperature increase (I don't imagine the bottom of the trench would get much sunlight).

The Earth has come closer to this scenario than you might think. During the Messinian salinity crisis, which began about six million years ago, the Strait of Gibraltar closed off and the Mediterranean Sea dried up into a sort of super Dead Sea, a hypersaline lake surrounded by a desertified abyssal basin where temperatures may have reached 80° C. Rivers that fed into the basin, like the Nile, cut deep gorges as they ran down to several kilometers below their current mouths. African species like hippopotami migrated across the basin before it got too hot and dry, then were stranded on cooler highlands like Malta and underwent island dwarfism. The crisis finally ended with the Zanclean flood, in which the sea refilled through the Strait of Gibraltar at a rate of about a thousand times the discharge rate of today's Amazon River.

A common trope in anime, video games, or other media is to depict the moon as much larger in the sky than in real life, often seeming to fill half the sky. If the moon were actually this large (or, alternately, this close to the earth), how would it affect life on earth, gravity, the tides, etc.?
Okay, maybe I was exaggerating a bit. This GIF is a less extreme example of what I'm talking about. Technically, with the right use of a zoom lens, it is possible to make the Moon appear this big relative to foreground objects. But assuming that's not the case in this image, let's try to estimate the angular size of the Moon. Let's assume that Inuyasha's (or whosever that is) seated figure is about four feet tall. Due to the lack of perspective it's impossible to know for sure how far we are from him (her?). I'll guess about twelve feet. This gives him an angular size of about 18.9°. The moon's angular size, then, is something like 9.9°. By way of comparison, the real Moon has a maximum angular size of about 0.57°.

This can't end well.

If we increase the size of the moon to match this new angular size but keep its distance the same, we get a new lunar mean radius of about 33,300 km, as opposed to 1,700 km for the real Moon. Or 6,300 km for the Earth. This truly super-Moon would be by far the largest rocky body in the Solar System. It would not orbit around the Earth; the Earth would orbit around it in just under three days. If we naively scale up the real moon in its proportions, this truly super Moon would have the mass of 87 Earths, nearly as much as Saturn, and a surface gravity of over 3 g. This moon would also have a gravity differential over the earth more than seven thousand times that of the regular moon, which would probably cause mile-high tides or something. (In real life, the earth would be tidally locked to the super-Moon just as the regular moon is to the earth)

If, on the other hand, we move the moon closer to the Earth so it appears this large, we get a new semimajor axis of 20,000 km, about 5% of the old semimajor axis of 384,000 km. This is just over three Earth radii and perilously close to the Moon's Roche limit, the distance at which tidal forces from the Earth tear the Moon apart and turn it into a ring system. It will have a new orbital period of less than eight hours and produce even higher tides than the super-Moon. Its gravity would probably also destabilize the orbits of satellites in geosynchronous orbit (which it would orbit beneath) and make it impossible to keep them up for long.

Here is an extreme example. Considering the fisheye effect in use here, let's suppose this moon has an angular size of 30°. Now things get really ridiculous. Scaling the moon up to these proportions gives it a ludicrous radius of 103,000 km, over a quarter of the distance to the Earth, and about 150% of the radius and eight times the mass of Jupiter. Its gravitational pull would cause your weight to tangibly fluctuate with the tides, which would be tens or hundreds of thousands of their current proportions. Again, I don't know the science involved with packing this must dirt together with these kinds of forces, but this is probably astrophysically impossible.

Moving the moon this close to earth puts it at a distance of just 6,500 km, giving it a new orbital period of less than 90 minutes and off-the-scale tides, but that doesn't matter because before you can get the Moon this close it will collide with the Earth and kill us all.

This is actually NASA's conception of the impact that created the Moon, but the actual result would be similar.
This is one way that I'm glad real life isn't more like anime.

What would happen if you could somehow connect two planets (say, Earth and Jupiter) with an unbreakable, unstretchable tether? Or an unbreakable, rigid girder?

Bad, bad things.

I wasn't sure how to answer this from a purely physical standpoint, so I wrote a quick Python simulation to model the situation. The results are interesting. If you connect the two planets at their point of conjunction (so they are about 4.2 AU apart), Earth basically acts a a pendulum hanging towards the Sun from Jupiter. Meanwhile, Jupiter's distance from the sun varies surprisingly regularly from about 5.3 AU to 4.64 AU over a 16-year year period; I think the Earth's swinging motion off the tether (which gets faster or slower as it gets closer to or farther from the Sun) acts somewhat like pumping your legs on a swing to go higher or lower; the force of the Sun's gravity on Earth, transmitted to Jupiter through the tether, either pulls it higher or lower in its orbit.

What this means for Earth is that instead of a normal year, it has a pendulum-like swing cycle that lasts about 10 months at its/Jupiter's furthest point from the Sun (where its distance varies from about 1 AU to 1.7 AU, beyond the orbit of Mars) and 4 months at their nearest approach (where the distance varies from about 0.45 to 1 AU, within the orbit of Mercury) with about 8 years elapsing between the high and low points of Earth/Jupiter's orbit. For reference, the habitable zone of the Solar System is (very roughly) around 0.75 AU to 1.4 AU. Earth's "orbit" will take it close enough to the Sun to boil the oceans and far enough away to freeze them. Presumably the atmosphere would exert some kind of moderating effect on these wild temperature swings, but things look pretty grim. There is also the risk of planetary collision with Mercury, Venus, and Mars to worry about.

If the Earth and Jupiter start out in opposition, then the tether obviously does nothing. (Even assuming it is indestructible and can survive passing through the Sun) What about if Earth and Jupiter start out 90° apart in their orbits?

That's not good.
On second thought, let's not build an unbreakable, unstretchable, indestructible tether to Jupiter.

What (roughly) would Mars look like with all the water we drained from the Earth's oceans on it? How would the water affect its climate?

Randall actually answered this one! (As asked by someone else)

What if every human being on earth used all their mechanical power (say, on exercise bicycles) to heat and boil the oceans? Would this have any noticeable effect on water levels or the weather? What if we also turned the power we generate from other sources (turbines, generators, cars, etc.) to this purpose?

The average power output of someone working hard is about 500 W. Assuming the fit people are able to balance out the infirm/children, the human race should be able to produce about 7 × 109 × 500 = 3.5 TW. Impressively, this is about a fifth of the total power consumption of the world, so the answers of the two parts of the question are more similar than I expected. Assuming we are boiling water from the surface of the ocean, which has an average temperature of 17 °C, we could boil about 1,334 tons of seawater per second. This becomes about 8,000 tons/second if we include our other means of generating power, which works out to roughly 250 km3 of water per year—just 0.05% of the global evapotranspiration caused by the sun. So it looks like the Sun wins this one. If we were smart enough to actually capture all that distilled water instead of letting it escape into the atmosphere and return as rain, though, we could solve California's water woes 34 times over. This sounds nice, but put another way it means that distilling enough water to satisfy California would require about 615 gigawatts, 3.8% of the energy generated worldwide. With that much power, we could power over 500 time machines to just go back in time and tell California to use less water.
In homage to
What would happen if you changed the rotational period of the Earth to one hour? Two hours? Half an hour? One minute?

This question was inspired by this one, in which Randall describes the catastrophic consequences of speeding the Earth's rotation so that a day lasts one second. So I wondered, what about some more moderate day lengths? What is the shortest day the Earth could have and still have things remain "normal"? Jupiter has a ten-hour day; at this angular speed, the Earth's surface would be moving at around 1.1 km/s instead of the usual 0.46 km/s. The effects of the centrifugal force would not be enough to noticeably counteract Earth's gravity, so the most catastrophic effect would be having to adjust to a ten-hour day.

A two-hour day would cut the Earth's apparent gravity in half. This would likely be awesome and extremely fun. Swimming and sports would be more exciting, people would travel by bunny-hopping everywhere, and we might already have flying cars. The effects would probably be similar to those of increased gravity as described by Randall in this answer, only reversed. On the other hand, the Coriolis effect would be much stronger, potentially increasing the incidence of hurricanes, and the atmosphere would be less dense, which might make it harder to enjoy your newfound antigravity powers.

You can't go much further than a two-hour day. At about 84 minutes (just over the length of a day in Skyrim), the centrifugal force at the equator equals the force of gravity. Long before this, the Earth would deform into an oblate spheroid (more noticeably than it already has) and accordingly slow its rotation. With a one-hour day or less, the Earth's mass around the Equator would break off and fly out into space (moving at escape velocity), though without the awesome consequences of the one-second day.

What would be the effects on Earth if its axial tilt were 90°, like that of Uranus?

Increasing the Earth's axial tilt from 23.5° to 90° would have some pretty drastic effects on the climate. As commentors in this discussion say, this would basically mean that the Equator and the Arctic/Antarctic circles would become the same. Everywhere on earth would get experience the midnight sun and polar night for part of the year. I'll break down what the day-night-year cycle would look like at a few select latitudes:
  • The Equator: Exactly 12 hours of daylight every day of the year (just like the real Equator), except on the solstices. The Sun's maximum elevation during these days ranges from 90° at the equinoxes (the Sun would travel directly across the middle of the sky) to very low around the solstices; it would just barely peek about the horizon, albeit for longer than it does at the real-life poles (still 12 hours). At the solstices, the Sun would circle the entire horizon without actually rising above it, creating 24-hour twilight. This Equator would probably have more extreme seasons than the real one; it would likely get quite cold at the solstices, and would be hot around the equinoxes much like in real life.
  • 30°: Two months of midnight sun, from about May 21st to July 21st, polar night from about November 21st to February 21st. Lahaina Noon on about August 21st and April 21st. At the Summer solstice, the Sun would hang at 30° in the sky all day; consequently, Summers would be surprisingly cool. Spring and Fall would be very hot due to the high insolation and winter would be bitterly cold, but this might end up being one of the more habitable latitudes.
  • 45°: Three months of midnight sun from about May 6th to August 6th, polar night from about November 6th to March 6th. The days of maximum insolation would also be May 6th and August 6th; on these days the Sun rises from the horizon at midnight to directly overhead at midday; these days would be sweltering. At the Summer solstice the Sun would stay at 45° all day. Late Spring and Summer would be brutal, but at least you get to look forward to three months of icy darkness to make up for it!
  • 65°: Near the real-life Arctic/Antarctic circles. Four-plus months of midnight sun, from about April 16th to August 26th, and polar night from about October 16th to February 24th. At the Summer solstice the Sun is at a constant 65° of elevation, and during the entire month of June it is at over 45° 24 hours a day. On May 26th and about July 14th, the Sun rises from 45° to directly overhead. In case you haven't noticed, things are getting worse the closer we get to the poles.
  • The North Pole: The Sun's elevation is constant throughout the day, every day. Six months of midnight sun, six months of polar night. We have no Earthly analogue for what the Summer solstice would be like: the Sun would stay over nearly the same point on the Earth's surface for weeks, causing unimaginable amounts of heating and evaporation. Meanwhile the Winters would be even colder than those of our poles.
In a nutshell, the seasons would become much more extreme than those of the real Earth the further you go away from the Equator. Closer to the Equator, the equinoxes would be hot (as hot as the real-life Equator) and the solstices would be cold, but not uninhabitably so. Most people would probably live close to the Equator. I don't feel qualified to speculate about the plant and animal life that would inhabit this alternate Earth. I really think Randall should answer this one; it would be a good counterpart to his fascinating article Cassini.

Wednesday, April 15, 2015

War and Peace

The following is the final(!) paper for my master's program, on the ethics of war and peace. (Not the book)

War is one of the oldest ethical questions that have faced Christians. Teaching on war has existed between two poles since the early days of the Church. The early Latin father Tertullian, speaking about the possibility of Christians serving in the military, unambiguously states that "there is no agreement between the divine and the human sacrament, the standard of Christ and the standard of the devil, the camp of light and the camp of darkness. One soul cannot be due to two masters—God and Caesar."1 Conversely, two hundred years later Augustine wrote, "it is the wrongdoing of the opposing party which compels the wise man to wage just wars."2 The traditions they represent, Christian pacifism and just war theory, have coexisted in the Church, sometimes uneasily, ever since.

Christian pacifism was a significant, though not dominant presence in the early church, as represented by fathers like Hippolytus, Tertullian, and Lactantius, and has remained so ever since.3 The pacifist tradition they helped originate was continued in the Middle Ages by the Waldensians and after the Reformation by Protestant denominations like the Mennonites, Swiss Brethren, and Quakers. In the modern era, reforming figures like Gandhi and Martin Luther King, Jr. have powerfully demonstrated the redemptive power of nonviolence to effect social change and publicly model the love of Christ. Christian pacifism "is more than simply approving of peace, which everyone in some sense would do, it is the conviction that the commitment to peace stands higher than any other commitment"4—even the commitment to seek justice.5

The biblical basis for Christian pacifism is centered on Jesus as "the image of the invisible God" (Col 1:15 RSV); he reveals the Father to us (Mat 11:27); he is God in the flesh, the final and greatest revelation of the divine (Heb 1:1-2). "He reflects the glory of God and bears the very stamp of his nature, upholding the universe by his word of power." (Heb 1:3) What is true of Jesus is true of God, and it is through the Incarnation that God has revealed to us both who he is and what it means to be truly human. And what kind of God does Jesus reveal to us? A God who responds to evil with mercy (Luk 15:11-32), who "makes his sun rise on the evil and on the good, and sends rain on the just and on the unjust" (Mat 5:45), who submitted to a horrific, unjust death on the cross, the ultimate demonstration of nonviolent love in the face of evil and an example for Christians to follow (1 Pet 2:21). The Incarnation is the "normative revelation of God" for Christians,6 and a major implication of it is that God is nonviolent.

Further support can be drawn from the teachings of Jesus. The first and most greatest commandment is to love God with all your heart, and inseparable from this is the command to love your neighbor as yourself. (Mat 22:34-40) But Jesus expands this command to include not just those we identify and get along with, but our enemies (Mat 5:43-45, Luk 6:35-36). We are to respond to evil, persecution, and violence not in kind, not with violent resistance (Mat 5:39) but with love and mercy. In doing so we are simply following the example of God, who loved us and showed us mercy (especially through Christ) when we were sinners and his enemies (5:8,10). These sharpened teachings are not simply unreachable ideals or general attitudes we are supposed to have; Jesus fully intended for us to obey them just as much as he intended for us to obey his command to love one another.

Commenting on and expanding Christ's teachings, Paul writes, "Love does no wrong to a neighbor; therefore love is the fulfilling of the law" (Rom 13:10) According to him, we are called to engage not in physical violence, but in spiritual warfare.7 (2 Cor 10:3-6) We must "Repay no one evil for evil...but overcome evil with good" (Rom 12:17,21). Violence, Christian pacifists argue, is not redemptive; it only leads to more evil, more violence, and so it can never positively advance the causes of justice or mercy. "The only ultimately redemptive response to sin and how it profoundly distorts human social life is, as Paul asserted, to seek to overcome evil with good (Romans 12). The only way successfully to resist violence without simply adding to violence in the world is overtly non-violent resistance."8 (Emphasis the author's)

While I support nearly all of the points made by Christian pacifism and believe that its Christ-centered message of peace needs to be heard more widely, I cannot follow its case to the absolute conclusion that war and violence are never permissible. In this it confuses private duties, in which a Christian is responsible foremost for his own soul, with public duties, in which a Christian, especially a parent or civil authority, is responsible for the protection of those in his care.9 One need look no further than the present situation in Iraq and Syria for an example of a situation in which an exclusive prescription of nonviolence would be impossibly idealistic (i.e. placing moral ideals before people), and for that reason heartless towards the vulnerable facing the real danger of violent persecution or death. For the sake of peace as the most important commitment and to avoid dirtying one's own hands, Christian pacifism is willing to allow death, suffering, and injustice to befall innocents. For the sake of loving one’s enemies, it is willing to compromise on loving neighbors, innocents, and those one may be charged to protect. Christ's teachings of pacifism and nonresistance are a high and vital calling for his followers, but to refuse to fight in the defense of others is to impose those teachings on those who, by and large, are not able to obey them to the utmost. It is to force martyrdom on them. To deny that such difficult choices ever have to be made is simply to deny the pervasive reality of sin in our world.

Christian pacifism also runs into some exegetical difficulties. It ignores Jesus' propensity to use hyperbole to accentuate his moral teachings; for example, I know of no one who has ever applied Matthew 5:29-30 literally and mutilated themselves to avoid sinning. Likewise his command to hate one's father and mother (Luk 14:26) is qualified by (among other things) his act of compassion on Mary from the cross in John 19:26-27, as well as Paul's command to provide for one's family (1 Tim 5:8). Its flat definition of Jesus as the "normative revelation of God" wanders dangerously close to Marcionism when it allows this reality to invalidate the depictions of God as blessing warfare in the Old Testament, reiterated in Heb 11:32-34. In context, its use of Romans 12 and 13 is also somewhat ambiguous: the justification for Christians not avenging themselves is not God's unwavering mercy but his self-declared monopoly on vengeance (Rom 12:19), and in Romans 13:1-7 Paul describes governing authorities as instituted by God, bearing the sword to execute his wrath (as a proxy) on the wrongdoer.

Thus even in the biblical support for Christian pacifism are found the seeds for just war theory, which holds that while war is evil, it may be permissible in certain circumstances. Augustine was the first to articulate the rationale that since the state is God's servant, appointed to bear the sword against wrongdoers (Rom 13:4), there are cases in which war (and capital punishment) can be just, in congruence with the examples of the Old Testament.10 Nonetheless war remains at best a lamentable necessity, an evil made permissible only by the presence of worse evils.11 The Scholastic theologian Thomas Aquinas built on the teachings of Augustine, going into more detail on the specific criteria that make a war “just” and reiterating that the aim of war is the restoration of peace and justice to the social order.12 The early reformers (except the aforementioned proponents of pacifism) continued to uphold the just-war tradition.

Just war theory distinguishes between at least two sets of criteria. Jus ad bellum criteria evaluate whether or not a given war is justifiable and include things like declaration by a competent authority, a just cause, proportionality of the means of war, exhaustion of peaceful means of resolution, and probability of success. Jus in bello criteria, including proportionality of force and discrimination of targets, are intended to minimize the evils of a war already in progress and avoid dehumanization of the enemy.13 Unlike Christian pacifism, just war theory does not hold that war always necessarily creates a worse evil than it overthrows, or that violence against a military opponent necessarily leads to hatred. It is possible to love one's enemies while using force to stop them from harming others, remaining ready (even eager) to lay down one's arms when peace is declared. God himself faces the same challenge of honoring and loving us (as his sacred image-bearers) even as we persist in destroying each other.

Just war theory enjoys plenty of biblical precedent, especially throughout the Old Testament, which presupposes that warfare can be legitimate. Abraham gets into a skirmish to rescue his nephew Lot (Gen 14:13-16), and is presented as an example of faith in the New Testament (Rom 4:11-12, Heb 11:8-30). The same can be said of Joshua (cf. Heb 11:30), the judges, and David (Heb 11:32-34), who are praised for their faith, including their willingness to fight in the name of God. In the New Testament, John the Baptist (Luk 3:14), Jesus (Luk 7:2-9), and Peter (Acts 10:1,24-48) have encounters with soldiers, in which we receive no hint that their profession is inherently sinful. As previously mentioned, in Romans 13:1-4 Paul states that governing authorities are servants instituted by God, appointed to bear the sword against wrongdoers. In John's apocalyptic vision Christ is depicted as one who "it is called Faithful and True, and in righteousness he judges and makes war." (Rev 19:11) "While the warfare in question is spiritual, nevertheless the suitability of the war metaphor implies that the activity itself is not a violation of the purposes of God. By way of contrast, God is never described as a 'harlot' or in terms of other occupations that are by their very nature immoral."14

Yet the logic of just war theory must not be taken too far. If overapplied, especially as a set of criteria for evaluating whether a given war is a "just" war, it risks becoming a moral "free pass" for war and killing, declaring them to be "good" when (as the destruction of God's image) they remain anything but. Just war theory can even end up sanctioning an implicit "end justifies the means" philosophy: if the end is considered to be "just", the horrors of war are declared "righteous". The Latin word iustus that is translated to "just" here should probably be taken to mean more "lawful", "legal", or "legitimate" in this case than positively "righteous", as is the connotation of the Greek dikaios. The point of Christian pacifism that violence is never redemptive is somewhat true; besides its destruction of the image of God, all war can do is prevent a greater evil or injustice by way of a (hopefully) lesser; this must not be confused with the actual creation of goodness or justice.

Both just war theory and Christian pacifism, when applied alone, have parallels with the kind of theodicy David Bentley Hart calls out for trying to make evil and suffering morally intelligible.15 The latter has echoes of a "greater good" theodicy: we are right to allow evil and injustice to occur in the short term for the sake of a longer-term good that cannot come about any other way. The suffering of innocents at the hands of the unjust is perversely necessary for the sake of the justice which, it is thought, can only come about through nonviolence. Conversely, just war theory can paint killing as "right" if it prevents a worse evil from occurring, which is dangerously relativistic. How can the Christian equally, consistently condemn and fight against all violence and injustice—both that within himself and that committed by others?

This tension is real, a consequence of the fallen world in which we live, and it is tempting to resolve it by simply adopting either a total pacifism that denounces all war as evil or a doctrine of "holy war" that makes (just) war into a positive norm. But the tension is an integral part of a truly biblical approach to war. Just (or perhaps "justifiable", or "permissible") war theory is good when it acknowledges that war is an evil and seeks to make it less so, and that any doctrine of war can only ever be a concession to human sinfulness. Yet war may be a necessary evil.16By pretending that we are already entirely free from war, we may unwittingly become culpable in even worse evils: Fr. David Alexander, an Orthodox chaplain in the U.S. Navy, says that "To fail to defend the innocent is paradoxically consenting to their elimination and extermination."17

Yet still more, the Christian pacifist tradition is needed as a voice of compassion and restraint even on our cautious dealings with war, a reminder of the potential of human sin and weakness to twist even the best intentions into dehumanizing atrocities. If just war theory is a concession to the reality of sin and human weakness, the voice of pacifism rings from a coming age without sin in which war will truly be obsolete—an age in which we within the Church already dwell, and into which we beckon all who will come in the name of the Lord (cf. Rev 22:17). Unlike just war theory, pacifism truly represents God's loving design for how we are ultimately made to live; any participation in war, even with the best intentions, falls short of this vision. In this evil age, sometimes it is necessary to fight; but as Christians, let us fight as those who have renounced violence (cf. 1 Cor 7:29-30), as ready and waiting to lay down our arms at the first chance of peace, as those looking forward to the final banquet where we will enjoy communion not only with our God and our neighbors, but with our enemies.

  1. Tertullian, On Idolatry, XIX, <> (11 April 2015).
  2. Augustine¸ The City of God, XIX.7, <> (11 April 2015).
  3. John Jefferson Davis, Evangelical Ethics (Phillipsburg, NJ: Presbyterian and Reformed Publishing, 2004), 242.
  4. Ted Grimsrud and Christian Early, "Christian Pacifism in Brief," Peace Theology, <> (14 April 2015).
  5. Davis, Evangelical Ethics, 243.
  6. Grimsrud and Early, "Christian Pacifism in Brief."
  7. Davis, Evangelical Ethics, 243.
  8. Grimsrud and Early, "Christian Pacifism in Brief."
  9. Davis, Evangelical Ethics, 246.
  10. Augustine, The City of God, I.21.
  11. Augustine, The City of God, XIX.7.
  12. Davis, Evangelical Ethics, 247.
  13. Kevin Allen, "Orthodoxy and War," Ancient Faith Radio, 11 August 2013, <> (7 April 2015) and Davis, Evangelical Ethics, 248.
  14. Davis, Evangelical Ethics, 250.
  15. David Bentley Hart, The Doors of the Sea: Where Was God in the Tsunami? (Grand Rapids: Eerdmans, 2005), 44,61.
  16. Fr. Stanley Harakas, “No Just War in the Fathers,” In Communion, 2 August 2005, <> (15 April 2015).
  17. Allen, "Orthodoxy and War."

Wednesday, April 8, 2015

My Journey, Part 16: Looking Back, Coming Home

This is the final part of my rebooted series on my journey from Evangelicalism to Eastern Orthodoxy. The full series can be found here:

1Back to the beginning
2Cracks appear
3Questions multiply
4Questioning the "gospel"
5The big question
6A better hermeneutic
7Explorations in epistemology
7.5Excursus on oversystematization
8Back to the gospel
9The new direction
10Ecclesiological foundations
11.1Sola scriptura
11.2The insufficiency of Scripture
11.25Addenda on sola scriptura
11.3Holy Tradition
12Bridging the cracks
13.1Orthodoxy and Genesis 1–3
13.2A Better Atonement (Against Penal Substitution)
13.3Faith Alone?
13.4The Colour and the Shape of the Gospel
14Worshipping with the Church
15Mary, Saints, Baptism, and Other Odds/Ends
16Looking Back, Coming Home

For this, the long-awaited (by no one more than me) last post in my chronicle of journeying to the Orthodox Church, I'm going to take an idea from my sister's blog and give it a soundtrack. What follows is best read with this song playing.


When I first started this series, I promised 35,000 words over "about 13 posts", "in relatively quick succession". What I instead produced ended up being about 112,000 words over 22 posts and eight months. I am terrible at estimating. To avoid forcing more people to read through them all, I'll summarize my trajectory here as briefly as I can.

Growing up in a Presbyterian church, I was apathetic about God for most of my life. When I first started caring about the faith I'd been raised in, I had picked up some misconceptions: the version of Christianity existing in my head was highly dualistic ("it's not about what I do, it's about what God has done", "all I can do is trust God and let him take care of the rest", etc.), rationalistic, inward-oriented, and reduced everything to the state of my all-important "relationship with God". It was a caricature of authentic Christianity, but I didn't know anything better at the time, and it was still an improvement from my former near-total apathy toward God.

In college I became involved with evangelical Christianity, which placed a strong emphasis on "making your faith your own" and "living it out" through intentionally following the teachings of Jesus, discipleship, and missions. In the course of following this calling, I ran into my first serious doubts in my newly personalized faith. First, my dualistic thinking led to great discouragement and doubt in the authenticity of my faith when I felt unable to see my obedience bearing any "fruit". Due to the pressure of the ministry I was involved in, I set this doubt aside, thinking I had conquered it. But the next year, I began questioning the point of it all: why do we seek to grow in relationship with God and introduce him to others? When does this become more than an activity or exercise and pervade the whole life? My other two misconceptions about my faith had begun to catch up with me; I went through a difficult time of doubt and rethinking of the ways I applied my faith, trying to make the inside and outside match better.

Reassessing the ways I was living my evangelical faith out, I realized many were more because of external pressure than any deep conviction within me. Rather than simply dismiss my uneasiness and remind myself that Christian living doesn't depend on feelings, I sought to reassess and deepen my beliefs to help them to make more sense to me, so that I could live my faith out more authentically. I wanted to make my "internal faith" match my "external faith".  But, turning to the Bible in hopes that it would help me to do this, it instead ended up giving me stronger, deeper doubts. I encountered passages that seemed to depict God telling people to sin, or outright lying—what was going on? God's own word seemed to be calling his goodness into question. I took a biblical theology class at my church in hopes that it would help, but as it took me on a tour through the Bible from cover to cover I instead got even more questions. Amid all of these, a "meta-question" burned in my mind: why do I have to struggle with the Bible so much to get it to make sense?

I "knew" that the all-important gospel was the key to making sense of the story of Scripture, but around this time (in 2012 and 2013) the account of the gospel I had been taught so often from a Reformed evangelical background also stopped making sense. I questioned its assessment of the "big problem" the gospel solves (universal, endemic sin and just condemnation) and its origin; I questioned the sensicality of the proposed solution (penal substitutionary atonement); I questioned the strong evangelical focus on securing individual "decisions for Christ" and "getting saved". Though the authors and blogs I read offered tantalizingly ethereal alternatives to the teachings that gave rise to these questions, I was plagued above all by the problem of Paul: his writings, more definitive of the "gospel" I was trying to make sense of than any other part of the Bible, seemed to be irreducibly at odds with the Old Testament; it made the gospel appear to be a solution to a problem that God himself created. And if this was true (as it seemed to be, inescapably), the whole thing stopped making any sense.

Finally, I got tired of my attempts to push all these doubts aside for the sake of not making my faith about an "intellectual assent" rather than a "relationship". I realized that by refusing to deal with my doubts or thinking that they were "just me", I was allowing them to eat away at my faith until there was very little left. Finally I confessed to God that he had stopped making any sense to me and that his word had contradictions in it. But a funny thing happened: I didn't simply despair at losing my faith. I realized that I still had faith in God, that it ran deeper than what I could rationally make sense of. The trust I still had in God that led me to pray to him—I realized that is what faith really is.

My confidence renewed by this realization, I set out to reconstruct the edifice of beliefs and theology that my doubts had pulled down. Taking plenty of inspiration from "post-evangelical" types like Peter Enns, I sought new paradigms for thinking about the Bible, God, and truth itself. To address my doubts head-on, I learned to read Scripture in its original cultural and historical context, via something Enns (and others like Christian Smith) call the "international hermeneutic". In search of a more humble epistemology that could see past all the denominational divisions between Christians (an area of increasing concern for me). I explored the implications of Jesus being the Truth (Jhn 14:6), and of truth therefore being bigger than what I can grasp with mere rationality. In my nerdier moments, I struggled to put into words the frustration I had with the tendency of evangelical theology to oversystematize things and pack weighty truths into convenient jargon. I looked for answers to my questions about the gospel, finding the New Perspective on Paul especially fruitful for reconciling Paul and the Old Testament. Yet I was frustrated by the individualism of my question, the implicit relativism of trying to construct a theology that made sense to me, and the academic, idealistic nature of my search for truth: even if I did find a vision of the gospel that had the ring of truth, where would I find a church that practiced it?

Then, through the master's program I was taking at the University of Northwestern, I stumbled upon both in the form of the Eastern Orthodox Church. The more I studied its teachings, the more I realized it was the church and the faith that I had been seeking for years, despite my initial doubts. Unlike the traditions I'd been weighing, it has the historical backing to support its claim to be the Church holding the Faith that Jesus founded two thousand years ago, claims that are a dime a dozen within the Reformation tradition. In its ecclesiology I saw the antidote to the metaphysical dualism, individualism, and divisions plaguing Protestant churches and their claims. In its approach to the Bible I saw the way past the doctrinal confusion and divisions sown by the ahistorical Protestant approach of sola scriptura; the answer is not Scripture alone, but Scripture at the center of the Holy Tradition of the Church, the body of Christ. Orthodoxy also exemplifies a more mystical, practical, incarnational approach to theology that is the perfect answer to the rationalism that divided my faith into interior and exterior dimensions and gave rise to my seemingly endless questions. It not simply a matter if believing the right things and then living or "applying" them; Orthodox spirituality is "real" (in the language of my doubts) to the core, and never heady.

But even as it has helped me see past the misconceptions that made my questions and doubts about evangelical Christianity seem so necessary and important, Orthodoxy has shown me a far better, more coherent, more intuitive, and more beautiful vision of the gospel than I had ever heard before, one which either makes my old questions unnecessary or replaces them with better ones. The Orthodox approach to Genesis is more compatible with modern science and makes clear that the "problem" of the gospel is not in any way God's doing, nor is it a total derailment of his purposes. The eastern telling of the gospel avoids the numerous problems of penal substitutionary atonement and instead offers a rich, multidimensional heritage of interpretations centering around Christ's defeat of sin, death, the devil, and all the spiritual forces that enslave and threaten humanity. It also offers an alternative to the various dichotomies (faith vs. works, law vs. gospel, human agency vs. divine agency) that contributed to my former confusion about how to "live out" the gospel, and the perhaps-excessive evangelical focus on "decisions for Christ" and the singular conversion experience. And finally, though it wasn't one of the reasons I initially felt drawn to Orthodoxy, I found its liturgical worship more beautiful, more historically grounded, and more consistently incarnational than a contemporary style.

Whither ecumenism?

Looking over previous posts (and even the previous iteration of this one), I keep noticing how I used to be much more concerned for the unity of the church than I am today. This is understandable, because I used to think that the church—the one, holy, catholic, and apostolic Church that Jesus founded—really is divided up into disparate denominations, communions, and confessions. I felt adrift in a sea of relativism, unable to find any solid answers to my questions of faith; whatever answer I preferred, there seemed to be a denomination, church, or (at least) theologian that supported and legitimated it. Though most claimed to be after this elusive beast called "biblical Christianity", I feared that it had been lost in the plurality of viewpoints.

But now I am blessed to see that the Church is not divided and biblical Christianity is not lost. God has not simply abandoned us to to try to derive the Christian faith for ourselves from first biblical principles. Rather, he is faithfully present with us through his Spirit which knits us together into the one, holy body of Christ, within which there can be no schism. Though the reunion of Christians is beneficial and highly desirable for many reasons, we do not "reunify" or "assemble" the Church by doing so. Protestants tend to consider it "arrogant" to claim to be the church that Christ founded, but consider the alternative! Such objections are little different from the relativist's argument that it is arrogant to make exclusive truth claims; I find it ironic that apologists who are so eager to defend "absolute truth" in epistemology are so reluctant to accept it when it comes to ecclesiology.

Moving forward, I face the challenge of continuing to be ecumenically-minded when when absolutely everything doesn't depend on it, as I used to think, and of pursuing unity humbly even while earnestly believing that this unity means everyone becoming Orthodox in some form. As I become more settled in the faith, I want to affirm it wherever I see it reflected in others, to learn to disagree constructively and charitably. Really, this has been my desire for years, but now I am called to do so even more and without compromising on my newfound certainty. In the end, I don't just want to cross over the gap between churches; I want to see it closed.

Looking back...

Through all of this transition, I've continued attending my old evangelical church and Bible study, which I consider a good thing. When I was just beginning to discover the riches of the Orthodox faith around a year ago, I was at risk of succumbing to "conversion sickness", becoming resentful of the tradition I was leaving and ignoring my own advice about not defining yourself by what you reject or disbelieve. I was not yet Orthodox, but I certainly felt "post-evangelical". Yet because of my continuing ties to it, I couldn't just fling criticisms at evangelicalism as from the outside. This was a tradition that many of my friends still belong to, that had been responsible for much of my own spiritual formation. How could I just step away and call it bankrupt? So as I continued to stay at least somewhat within the evangelical bubble, I felt called to make peace with my old tradition, albeit as an ecumenically-minded outsider to it: to affirm and encourage the good within it without feeling threatened or offended by the bad as I used to. So I started to think about things that evangelicalism does get right. Somewhat to my surprise, this list was not empty.

Engaging and redeeming culture. While I do prefer the traditional, liturgical, a capella worship of the Orthodox Church, this doesn't mean that more contemporary styles of music are outside the scope of the gospel. Though not always for the right reasons, evangelicals tend to be quite open to contemporary culture and seek to engage with it constructively. This is a truly scriptural impulse, based as it is on the universal scope of redemption, and in many ways better than the traditional Orthodox mentality which is content to let culture pass it by to preserve its traditions untouched. In their better, more creative moments, I think evangelical can teach Orthodox a thing or do about approaching and redeeming the culture around them from within.

Biblical/textual study. Even many Orthodox admit that Protestants, especially "Bible-believing" ones, tend to have a higher standard of biblical literacy for laypeople; all that emphasis on reading the Bible for yourself every day is really good for something. I've not sure how much background knowledge of the Bible I would have if I'd grown up Orthodox. A huge amount of academically solid biblical and theological studies go on in Protestant schools (again, their separation from the Church is unfortunate), and most textual criticism of the Bible is done by Protestants; English-speaking Orthodox mostly use Bible translations created by Protestant scholars, such as the RSV (which has also been approved for use by the Catholic Church). Of course this knowledge can be used to blaze your own path of personal interpretations away from the rest of the Church, maybe even taking others with you, but with the right attitude it is a precious resource.

Proselytizing/widespread willingness to go, even on missions. It's hard to deny that evangelicals take Jesus command to go in Matthew 28:19 very seriously. I had trouble going along with this constant push toward missions because a) it felt overwhelming at times, b) the main form of "evangelism" I heard about was walking up to strangers to start "spiritual conversations" with them, and c) the "gospel" I was supposed to be sharing didn't make sense to me. But the evangelical argument that you should be eager to share the best news of your life with people still holds. Even the prominent magician/atheist Penn Jillette acknowledges that if you really believe that the gospel is the best news anyone can ever hear, then you should be sharing it. As I've been taking in more of the Orthodox faith, I have started to notice myself really wishing that others could know it as well and for ways to share it—an impulse that was largely external in evangelicalism, but now comes from within.

An emphasis on personal, authentic, lived faith. If I had to pick the greatest strength of evangelicalism (and the greatest contribution of western individualism to Christianity), this would be it. Though language of Christianity as a "personal commitment/decision/relationship" is often used erroneously or reductionistically, the truth is that Christianity is all of these things, though it is also much more. If evangelical Christianity had not deeply impressed on me the importance of personal applicability, authenticity, and practical, ground-level application in my faith, it's likely I would never have found the Orthodox Church, or even looked for it.

I hope my continuing relationship with evangelical (and Protestant) Christianity is a long and fruitful one.

Coming home

"For everything there is a season, and a time for every matter under heaven", says the preacher. (Ecc 3:1),
a time to be born, and a time to die; a time to plant, and a time to pluck up what is planted;
a time to kill, and a time to heal; a time to break down, and a time to build up;
a time to weep, and a time to laugh; a time to mourn, and a time to dance;
a time to cast away stones, and a time to gather stones together; a time to embrace, and a time to refrain from embracing;
a time to seek, and a time to lose; a time to keep, and a time to cast away;
a time to rend, and a time to sew; a time to keep silence, and a time to speak;
a time to love, and a time to hate; a time for war, and a time for peace. (3:2-7)
To these I might add: "a time to doubt, and a time to put away doubt." When I stopped denying my doubt and started trying to truly address it, I adopted a very positive view of doubt, as something healthy, necessary, and normal. I also cautioned against excessive or "bad" doubt, and now I see this danger clearly. Doubt can be the chisel by which God carves away our unworthy beliefs, attitudes, and habits, or it can be our excuse for hesitating and ignoring our conscience. But while I still agree with all of this, it turns out I had my definitions reversed. Experiencing "good" doubt (uncertainty and skepticism) is actually a bad sign insofar as the thing you are doubting is worth doubting; experiencing "bad" doubt (hesitation and aversion) is actually a good thing insofar as the thing you are doubting is worth actively pursuing. (Jesus himself seemed to experience it; Mat 26:39) So I count it a blessing that I very rarely experience "good" doubt about Orthodox teaching; the challenge is no longer forcing myself to believe it or getting it to make sense to me, but consistently abiding by it, the test of every spiritual athlete.

In biblical studies, there is a literary technique called chiasmus in which a pattern is repeated in inverted order, which gives the text a concentric structure which (in some cases) can be quite elaborate. Looking back over my story, I can see this structure in it. When I first started to be intentional about my faith, I was concerned with matters of practice, with consistently living what I saw as the truth. But as my doubts grew, my faith turned more and more inward as I questioned what "the truth" really was. Now this questioning is very nearly over, and in many ways I'm back to where I started, with a lot more clarity and conviction. As I hoped and prayed, I have found a vision of the Christian faith which I can wholeheartedly believe, but this is only the starting point for the real journey it reveals stretching out before me—a path heavily trod by past generations of saints, leading ever upward to God.