Tag Archives: environment

My Research with Steve

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Almost four years ago I took a job as a summer student of Dr. Steve Easterbrook, in the software engineering lab of the University of Toronto. This was my first time taking part in research, but also my first time living away from home and my first time using a Unix terminal (both of which are challenging, but immensely rewarding, life skills).

While working with Steve I discovered that climate model output is really pretty (an opinion which hasn’t changed in the four years since) and that climate models are really hard to install (that hasn’t changed either).

At Steve’s suggestion I got a hold of the code for various climate models and started to pick it apart. By the end of the summer I had created a series of standardised diagrams showing the software architecture of each model.

These diagrams proved to be really useful communication tools: we presented our work at AGU the following December, and at NCAR about a year after that, to very positive feedback. Many climate modellers we met at these conferences were pleased to have a software diagram of the model they used (which is very useful to show during presentations), but they were generally more interested in the diagrams for other models, to see how other research groups used different software structures to solve the same problems. “I had no idea they did it like that,” was a remark I heard more than a few times.

Between my undergrad and PhD, I went back to Toronto for a month where I analysed the model code more rigorously. We made a new set of diagrams which was more accurate: the code was sorted into components based on dependency structure, and the area of each component in a given diagram was exactly proportional to the line count of its source code.

Here is the diagram we made for the GFDL-ESM2M model, which is developed at the Geophysical Fluid Dynamics Laboratory in Princeton:

Figure 2 of Alexander et al., 2015

We wrote this all up into a paper, submitted it to GMD, and after several months and several rounds of revision it was published just yesterday! The paper is open access, and can be downloaded for free here. It’s my first paper as lead author which is pretty exciting.

I could go on about all the interesting things we discovered while comparing the diagrams, but that’s all in the paper. Instead I wanted to talk about what’s not in the paper: the story of the long and winding journey we took to get there, from my first day as a nervous summer student in Toronto to the final publication yesterday. These are the stories you don’t read about in scientific papers, which out of necessity detail the methodology as if the authors knew exactly where they were going and got there using the shortest possible path. Science doesn’t often work like that. Science is about messing around and exploring and getting a bit lost and eventually figuring it out and feeling like a superhero when you do. And then writing it up as if it was easy.

I also wanted to express my gratitude to Steve, who has been an amazing source of support, advice, conversations, book recommendations, introductions to scientists, and career advice. I’m so happy that I got to be your student. See you before long on one continent or another!

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My Cartoon Supervisors

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My supervisors are so distinguished that they now exist in cartoon form! If that’s not the mark of a successful science communicator, I’m not sure what is.

Here is Katrin:

And here is Matt:

A former supervisor of mine also got a cartoon:

There are 97 cartoons like this over at Skeptical Science, a site which is quickly becoming a force of nature. This campaign reached millions of people through Twitter alone, and was even retweeted by President Obama.

A New Chapter

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It has been a very busy few months. Here are some of the things I have done since I last wrote:

  • Moved out of our apartment in Canada
  • Spent three weeks in Ireland with my partner’s family – this was great fun and featured lots of music, tide pools, castles, and sheep
  • Went back to Canada for six days
  • Mastered the art of packing checked luggage and carry-on bags so they are juuust under the weight limit
  • Said a lot of tearful goodbyes
  • Flew to Australia!
  • Discovered Sydney was 11°C and raining
  • Immediately regretted leaving all our warm sweaters behind (“It’s spring in Australia,” we said. “We won’t need these for months yet,” we said)
  • Saw all three animals I had missed the most – bats, lorikeets, and scientists – in the very first day
  • Officially enrolled as a PhD student at UNSW
  • Stumbled into the Sydney real estate market, where rent prices are more than double what we are used to, and only the wealthiest people can afford to buy property
  • Managed to find a great little apartment for rent within our budget
  • Bought out most of IKEA
  • Moved into said apartment (we’re getting good at this moving thing)
  • Helped to finish up 3 papers from the project Katrin, Tim, and I did last year, and 1 paper from the project Steve and I did 3 years ago
  • Read at least a dozen papers on interactions between Antarctic ice shelves and the Southern Ocean – my PhD project will be somewhere in this field
  • Gone out for climate beers (regular beers consumed by climate scientists) and discussed whether the Canadian or the Australian political system is more fundamentally broken
  • Swam in the ocean three times, and discovered that if you put on goggles and look underneath the water you can see FISH swimming around beneath you

Things are finally calming down now, and I should have time to write more frequently. Now that my head is not so full of flight schedules and rental agreements and shopping lists, it has a lot more space for climate science, and for topics to write about here.

I am so, so happy to be back at the CCRC. It is such a friendly, supportive, and enriching place to do research. While I miss my family and the Canadian wildlife and Canadian autumn (definitely not Canadian winter), this is the best time in my life to travel and explore the planet which I spend so much time studying, and hopefully, helping.

The Arctic Has Barfed

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I was scanning my blog stats the other day – partly to see if people were reading my new post on the Blue Mountains bushfires, partly because I just like graphs – when I noticed that an article I wrote nearly two years ago was suddenly getting more views than ever before:

The article in question highlights the scientific inaccuracies of the 2004 film The Day After Tomorrow, in which global warming leads to a new ice age. Now that I’ve taken more courses in thermodynamics I could definitely expand on the original post if I had the time and inclination to watch the film again…

I did a bit more digging in my stats and discovered that most viewers are reaching this article through Google searches such as “is the day after tomorrow true”, “is the day after tomorrow likely to happen”, and “movie review of a day after tomorrow if it is possible or impossible.” The answers are no, no, and impossible, respectively.

But why the sudden surge in interest? I think it is probably related to the record cold temperatures across much of the United States, an event which media outlets have dubbed the “polar vortex”. I prefer “Arctic barf”.

Part of the extremely cold air mass which covers the Arctic has essentially detached and spilled southward over North America. In other words, the Arctic has barfed on the USA. Less sexy terminology than “polar vortex”, perhaps, but I would argue it is more enlightening.

Greg Laden also has a good explanation:

The Polar Vortex, a huge system of swirling air that normally contains the polar cold air has shifted so it is not sitting right on the pole as it usually does. We are not seeing an expansion of cold, an ice age, or an anti-global warming phenomenon. We are seeing the usual cold polar air taking an excursion.

Note that other regions such as Alaska and much of Europe are currently experiencing unusually warm winter weather. On balance, the planet isn’t any colder than normal. The cold patches are just moving around in an unusual way.

Having grown up in the Canadian Prairies, where we experience daily lows below -30°C for at least a few days each year (and for nearly a month straight so far this winter), I can’t say I have a lot of sympathy. Or maybe I’m just bitter because I never got a day off school due to the cold? But seriously, nothing has to shut down if you plug in the cars at night and bundle up like an astronaut. We’ve been doing it for years.

The Blue Mountains, Then and Now

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During our time in Australia, my partner and I decided on a whim to spend a weekend in the Blue Mountains. This national park, a two-hour train ride west of Sydney, forms part of the Great Dividing Range: a chain of mountains which stretches from north to south across the entire country, separating the vast outback to the west from the narrow strip of coastal rainforest to the east.

For a region so close to Sydney, the Blue Mountains feel surprisingly remote. You can stand at any number of clifftops, gaze out over a seemingly endless stretch of land, and see no sign of civilization whatsoever. Or you can walk down into the valleys between the mountains and explore the rainforest, a vast expanse of ancient gumtrees that’s managed to hide koalas previously thought to have vanished, and possibly even an escaped panther.

Four months later, when we were safely back in Canada, the Blue Mountains bushfires began. It was October, barely even spring in the Southern Hemisphere. To have fires starting so early in the season was virtually unheard of.

The triggers for the fires were decidedly human-caused: arson, a botched army exercise, and sparking power lines. However, unusually hot, dry, and windy conditions allowed the fires to spread far more quickly than they would have in a more normal October.

To get from the clifftops of Echo Point to the walking trails in the valley below, we took the Giant Stairway, which is exactly what it sounds like. Imagine the steepest and narrowest stairway you can manage, cut into the stone cliff and reinforced with metal, and a handrail which you cling to for dear life. Make it 902 stairs long (by my count, so let’s say plus or minus 5) and wind it back and forth around the cliff. After a few minutes walking down the stairway your knees start to buckle, and you require more and longer breaks, but you still can’t see the bottom.

The exhaustion is worth it simply due to the view.

Sometimes we would see swarms of sulfur-crested cockatoos flying over the treetops hundreds of metres below. They looked like tiny white specks at such a distance, but we could still hear them squawking to one another.

The bushfires of 2013 didn’t affect any of the areas we visited in the Blue Mountains – in fact, none of the main tourism regions were damaged. The main losses occurred in residential areas in and around the Blue Mountains. As of October 19th, 208 houses and 40 non-residential buildings had been destroyed.

Despite the huge amount of property loss, there were only two fatalities from the bushfires. This relatively successful outcome was due to mass evacuations organized by the government of New South Wales. At one point a state of emergency was declared, which authorized police to force residents to leave their houses.

As the fires continued to burn out of control, westerly winds blew the smoke and ash right over Sydney. During sunsets the sky over Sydney Harbour turned a bright orange, giving the illusion of a city built on the surface of Mars.

I had heard about lyre birds, widely considered to be among the best mimics of the animal kingdom, many times before. In an elaborate courtship display, the male lyre bird perfectly imitates the songs of nearly every other bird in the forest, one after another like some kind of avian pop-music mashup. Lyre birds blow mockingbirds right out of the water.

Footage from the BBC of a lyre bird imitating camera shutters and chainsaws seemed too good to be true, but its authenticity was bolstered by a similar story from my friend at the climate lab in Sydney. Her neighbours had been doing renovations, and when they were finished the construction equipment went away but the sounds kept going. That’s when they discovered the lyre bird living in the garden.

We saw three or four lyre birds while hiking in the valley that weekend, but for the most part they just wandered around the forest floor, combing through the leaf litter with an outstretched foot and keeping their beaks firmly shut. It was winter in Australia, after all – not courtship season for most birds. On the last day of hiking, we sat by the side of the trail for a rest and a drink of water, while my partner quizzed me on the local bird calls.

“What kind of bird is making that song?”

“An eastern whip-bird, I think.

“Hang on, it just changed into a kookaburra.

“And now it’s a currawong?”

A few minutes later, a male lyre bird strolled out onto the path ahead of us, showing off his fantastic tail feathers and looking extremely pleased with himself.

It is well known among scientists that human-caused climate change increases the risk of severe bushfires. Spells of hot weather will obviously become more common as the planet warms, but so will prolonged droughts, especially in subtropical regions like Australia. Add an initial trigger, like a lightning strike or an abandoned campfire, and you have the perfect recipe for a bushfire.

The current Australian government, which has a history of questionable statements on climate change, really doesn’t want to believe this. Prime Minister Tony Abbott asserted that “these fires are certainly not a function of climate change, they’re a function of life in Australia”, while Environment Minister Greg Hunt cited Wikipedia during a similar statement. I was actually heartened by these events: the ensuing public outcry convinced me that Australians, by and large, do not buy into their government’s indifference on this issue.

It came as a surprise to nobody in the climate science community, and probably nobody in Australia, that 2013 was Australia’s warmest year on record. The previous record, set in 2005, was exceeded by a fairly significant 0.17°C. Even more remarkable was the fact that 2013 was an ENSO-neutral year. For Australia to shatter this temperature record without the help of El Niño indicates that something else (*cough cough climate change*) is at work.

Would the Blue Mountains bushfires have been so devastating without the help of human-caused climate change? In a cooler and wetter October, closer to the historical average, would the initial fire triggers have developed into anything significant? We’ll never know for sure. What we can say, though, is that bushfires like these will only become more common as climate change continues. This is what the future will look like.

Bits and Pieces

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Now that the academic summer is over, I have left Australia and returned home to Canada. It is great to be with my friends and family again, but I really miss the ocean and the giant monster bats. Not to mention the lab: after four months as a proper scientist, it’s very hard to be an undergrad again.

While I continue to settle in, move to a new apartment, and recover from jet lag (which is way worse in this direction!), here are a few pieces of reading to tide you over:

Scott Johnson from Ars Technica wrote a fabulous piece about climate modelling, and the process by which scientists build and test new components. The article is accurate and compelling, and features interviews with two of my former supervisors (Steve Easterbrook and Andrew Weaver) and lots of other great communicators (Gavin Schmidt and Richard Alley, to name a few).

I have just started reading A Short History of Nearly Everything by Bill Bryson. So far, it is one of the best pieces of science writing I have ever read. As well as being funny and easy to understand, it makes me excited about areas of science I haven’t studied since high school.

Finally, my third and final paper from last summer in Victoria was published in the August edition of Journal of Climate. The full text (subscription required) is available here. It is a companion paper to our recent Climate of the Past study, and compares the projections of EMICs (Earth System Models of Intermediate Complexity) when forced with different RCP scenarios. In a nutshell, we found that even after anthropogenic emissions fall to zero, it takes a very long time for CO2 concentrations to recover, even longer for global temperatures to start falling, and longer still for sea level rise (caused by thermal expansion alone, i.e. neglecting the melting of ice sheets) to stabilize, let alone reverse.

Well, This is a Problem

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The back gardens of Mayflower, Arkansas aren’t looking too good:

spill

Yes, that’s oil. Canadian oil, no less. You’re welcome.

I’ve heard surprisingly little about this event, which occurred when an Exxon Mobil pipeline ruptured on Friday. It appears that the press have limited access while the cleanup crews are at work. National Geographic had a good piece, though.

Call me cynical, but I think the Canadian media are purposely keeping quiet on this one. It’s a very inconvenient time for a pipeline to burst, given that all levels of government and industry are pushing for Keystone, Northern Gateway, Energy East, etc., etc.

News of this event is largely relying on Mayflower citizens leveraging social media. There’s no way to verify their photos and videos, but they’re striking nonetheless. Here’s a video of the situation on a residential street – note the lack of cleanup crews.

The oil is going straight into the storm drain, the man in the video says, which makes me shudder. I don’t know anything about Mayflower’s stormwater system, but where I live those storm drains are about three steps removed from the Red River. Once oil got in there, I can’t imagine it ever getting out.

I find it puzzling that the negative impacts of pipelines are so often catalogued as “environmentalists’ problems” in the Canadian media – here’s a typical example. In reality, they’re everyone’s problems. Environmentalists (as much as I detest that label) are just the people who realize it. We are not a special interest group; we represent everyone. When it comes to disasters, from short-term spills like the one in Mayflower to millennial-scale impacts like climate change, Canadian oil will affect everyone indiscriminately.

Side note: Sorry I have been so absurdly quiet recently. I am busy building two climate models – just small ones for term projects, but so enjoyable that everything else is getting neglected. I’ll be posting much more on that in about a month.

Climate change and the jet stream

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Here in the northern mid-latitudes (much of Canada and the US, Europe, and the northern half of Asia) our weather is governed by the jet stream. This high-altitude wind current, flowing rapidly from west to east, separates cold Arctic air (to the north) from warmer temperate air (to the south). So on a given day, if you’re north of the jet stream, the weather will probably be cold; if you’re to the south, it will probably be warm; and if the jet stream is passing over you, you’re likely to get rain or snow.

The jet stream isn’t straight, though; it’s rather wavy in the north-south direction, with peaks and troughs. So it’s entirely possible for Calgary to experience a cold spell (sitting in a trough of the jet stream) while Winnipeg, almost directly to the east, has a heat wave (sitting in a peak). The farther north and south these peaks and troughs extend, the more extreme these temperature anomalies tend to be.

Sometimes a large peak or trough will hang around for weeks on end, held in place by certain air pressure patterns. This phenomenon is known as “blocking”, and is often associated with extreme weather. For example, the 2010 heat wave in Russia coincided with a large, stationary, long-lived peak in the polar jet stream. Wildfires, heat stroke, and crop failure ensued. Not a pretty picture.

As climate change adds more energy to the atmosphere, it would be naive to expect all the wind currents to stay exactly the same. Predicting the changes is a complicated business, but a recent study by Jennifer Francis and Stephen Vavrus made headway on the polar jet stream. Using North American and North Atlantic atmospheric reanalyses (models forced with observations rather than a spin-up) from 1979-2010, they found that Arctic amplification – the faster rate at which the Arctic warms, compared to the rest of the world – makes the jet stream slower and wavier. As a result, blocking events become more likely.

Arctic amplification occurs because of the ice-albedo effect: there is more snow and ice available in the Arctic to melt and decrease the albedo of the region. (Faster-than-average warming is not seen in much of Antarctica, because a great deal of thermal inertia is provided to the continent in the form of strong circumpolar wind and ocean currents.) This amplification is particularly strong in autumn and winter.

Now, remembering that atmospheric pressure is directly related to temperature, and pressure decreases with height, warming a region will increase the height at which pressure falls to 500 hPa. (That is, it will raise the 500 hPa “ceiling”.) Below that, the 1000 hPa ceiling doesn’t rise very much, because surface pressure doesn’t usually go much above 1000 hPa anyway. So in total, the vertical portion of the atmosphere that falls between 1000 and 500 hPa becomes thicker as a result of warming.

Since the Arctic is warming faster than the midlatitudes to the south, the temperature difference between these two regions is smaller. Therefore, the difference in 1000-500 hPa thickness is also smaller. Running through a lot of complicated physics equations, this has two main effects:

  1. Winds in the east-west direction (including the jet stream) travel more slowly.
  2. Peaks of the jet stream are pulled farther north, making the current wavier.

Also, both of these effects reinforce each other: slow jet streams tend to be wavier, and wavy jet streams tend to travel more slowly. The correlation between relative 1000-500 hPa thickness and these two effects is not statistically significant in spring, but it is in the other three seasons. Also, melting sea ice and declining snow cover on land are well correlated to relative 1000-500 hPa thickness, which makes sense because these changes are the drivers of Arctic amplification.

Consequently, there is now data to back up the hypothesis that climate change is causing more extreme fall and winter weather in the mid-latitudes, and in both directions: unusual cold as well as unusual heat. Saying that global warming can cause regional cold spells is not a nefarious move by climate scientists in an attempt to make every possible outcome support their theory, as some paranoid pundits have claimed. Rather, it is another step in our understanding of a complex, non-linear system with high regional variability.

Many recent events, such as record snowfalls in the US during the winters of 2009-10 and 2010-11, are consistent with this mechanism – it’s easy to see that they were caused by blocking in the jet stream when Arctic amplification was particularly high. They may or may not have happened anyway, if climate change wasn’t in the picture. However, if this hypothesis endures, we can expect more extreme weather from all sides – hotter, colder, wetter, drier – as climate change continues. Don’t throw away your snow shovels just yet.

Permafrost Projections

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During my summer at UVic, two PhD students at the lab (Andrew MacDougall and Chris Avis) as well as my supervisor (Andrew Weaver) wrote a paper modelling the permafrost carbon feedback, which was recently published in Nature Geoscience. I read a draft version of this paper several months ago, and am very excited to finally share it here.

Studying the permafrost carbon feedback is at once exciting (because it has been left out of climate models for so long) and terrifying (because it has the potential to be a real game-changer). There is about twice as much carbon frozen into permafrost than there is floating around in the entire atmosphere. As high CO2 levels cause the world to warm, some of the permafrost will thaw and release this carbon as more CO2 – causing more warming, and so on. Previous climate model simulations involving permafrost have measured the CO2 released during thaw, but haven’t actually applied it to the atmosphere and allowed it to change the climate. This UVic study is the first to close that feedback loop (in climate model speak we call this “fully coupled”).

The permafrost part of the land component was already in place – it was developed for Chris’s PhD thesis, and implemented in a previous paper. It involves converting the existing single-layer soil model to a multi-layer model where some layers can be frozen year-round. Also, instead of the four RCP scenarios, the authors used DEPs (Diagnosed Emission Pathways): exactly the same as RCPs, except that CO2 emissions, rather than concentrations, are given to the model as input. This was necessary so that extra emissions from permafrost thaw would be taken into account by concentration values calculated at the time.

As a result, permafrost added an extra 44, 104, 185, and 279 ppm of CO2 to the atmosphere for DEP 2.6, 4.5, 6.0, and 8.5 respectively. However, the extra warming by 2100 was about the same for each DEP, with central estimates around 0.25 °C. Interestingly, the logarithmic effect of CO2 on climate (adding 10 ppm to the atmosphere causes more warming when the background concentration is 300 ppm than when it is 400 ppm) managed to cancel out the increasing amounts of permafrost thaw. By 2300, the central estimates of extra warming were more variable, and ranged from 0.13 to 1.69 °C when full uncertainty ranges were taken into account. Altering climate sensitivity (by means of an artificial feedback), in particular, had a large effect.

As a result of the thawing permafrost, the land switched from a carbon sink (net CO2 absorber) to a carbon source (net CO2 emitter) decades earlier than it would have otherwise – before 2100 for every DEP. The ocean kept absorbing carbon, but in some scenarios the carbon source of the land outweighed the carbon sink of the ocean. That is, even without human emissions, the land was emitting more CO2 than the ocean could soak up. Concentrations kept climbing indefinitely, even if human emissions suddenly dropped to zero. This is the part of the paper that made me want to hide under my desk.

This scenario wasn’t too hard to reach, either – if climate sensitivity was greater than 3°C warming per doubling of CO2 (about a 50% chance, as 3°C is the median estimate by scientists today), and people followed DEP 8.5 to at least 2013 before stopping all emissions (a very intense scenario, but I wouldn’t underestimate our ability to dig up fossil fuels and burn them really fast), permafrost thaw ensured that CO2 concentrations kept rising on their own in a self-sustaining loop. The scenarios didn’t run past 2300, but I’m sure that if you left it long enough the ocean would eventually win and CO2 would start to fall. The ocean always wins in the end, but things can be pretty nasty until then.

As if that weren’t enough, the paper goes on to list a whole bunch of reasons why their values are likely underestimates. For example, they assumed that all emissions from permafrost were  CO2, rather than the much stronger CH4 which is easily produced in oxygen-depleted soil; the UVic model is also known to underestimate Arctic amplification of climate change (how much faster the Arctic warms than the rest of the planet). Most of the uncertainties – and there are many – are in the direction we don’t want, suggesting that the problem will be worse than what we see in the model.

This paper went in my mental “oh shit” folder, because it made me realize that we are starting to lose control over the climate system. No matter what path we follow – even if we manage slightly negative emissions, i.e. artificially removing CO2 from the atmosphere – this model suggests we’ve got an extra 0.25°C in the pipeline due to permafrost. It doesn’t sound like much, but add that to the 0.8°C we’ve already seen, and take technological inertia into account (it’s simply not feasible to stop all emissions overnight), and we’re coming perilously close to the big nonlinearity (i.e. tipping point) that many argue is between 1.5 and 2°C. Take political inertia into account (most governments are nowhere near even creating a plan to reduce emissions), and we’ve long passed it.

Just because we’re probably going to miss the the first tipping point, though, doesn’t mean we should throw up our hands and give up. 2°C is bad, but 5°C is awful, and 10°C is unthinkable. The situation can always get worse if we let it, and how irresponsible would it be if we did?

A Bad Situation in the Arctic

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Arctic sea ice is in the midst of a record-breaking melt season. This is yet another symptom of human-caused climate change progressing much faster than scientists anticipated.

Every year, the frozen surface of the Arctic Ocean waxes and wanes, covering the largest area in February or March and the smallest in September. Over the past few decades, these September minima have been getting smaller and smaller. The lowest sea ice extent on record occurred in 2007, followed closely by 2011, 2008, 2010, and 2009. That is, the five lowest years on record all happened in the past five years. While year-to-year weather conditions, like summer storms, impact the variability of Arctic sea ice cover, the undeniable downward trend can only be explained by human-caused climate change.

The 2012 melt season started off hopefully, with April sea ice extent near the 1979-2000 average. Then things took a turn for the worse, and sea ice was at record or near-record low conditions for most of the summer. In early August, a storm spread out the remaining ice, exacerbating the melt. Currently, sea ice is significantly below the previous record for this time of year. See the light blue line in the figure below:

The 2012 minimum is already the fifth-lowest on record for any day of the year – and the worst part is, it will keep melting for about another month. At this rate, it’s looking pretty likely that we’ll break the 2007 record and hit an all-time low in September. Sea ice volume, rather than extent, is in the same situation.

Computer models of the climate system have a difficult time reproducing this sudden melt. As recently as 2007, the absolute worst-case projections showed summer Arctic sea ice disappearing around 2100. Based on observations, scientists are now confident that will happen well before 2050, and possibly within a decade. Climate models, which many pundits like to dismiss as “alarmist,” actually underestimated the severity of the problem. Uncertainty cuts both ways.

The impacts of an ice-free Arctic Ocean will be wide-ranging and severe. Luckily, melting sea ice does not contribute to sea level rise (only landlocked ice does, such as the Greenland and Antarctic ice sheets), but many other problems remain. The Inuit peoples of the north, who depend on sea ice for hunting, will lose an essential source of food and culture. Geopolitical tensions regarding ownership of the newly-accessible Arctic waters are likely. Changes to the Arctic food web, from blooming phytoplankton to dwindling polar bears, will irreversibly alter the ecosystem. While scientists don’t know exactly what this new Arctic will look like, it is certain to involve a great deal of disruption and suffering.

Daily updates on Arctic sea ice conditions are available from the NSIDC website.