The Climate in Emergency

A weekly blog on science, news, and ideas related to climate change


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What’s Hot, These Days

Over the last month or so, while I’ve been preoccupied with disasters closer to home, a series of alarming articles have wafted across my social media feeds–articles with titles like:

  • The Arctic Is Burning!
  • The Arctic Is Melting!
  • This Was the Hottest July on Record!

Alarmism? No, not at all. We live in alarming times, is all. But it’s high time I got caught up. I’ll catch you up in the process, just in case I’m not the only one who was more or less unavailable for a month or so. Then we can get on with talking about ideas, issues, and events in more detail.

News

Let me catch us up.

Fire in a Cold Place

The earliest article on the arctic fires I could find dates from July 13th and includes satellite images of smoke and fire taken that day. The article is a little vague as to exactly when the fires had started burning and whether the story was actually about a few large, long-burning fires or many brief, small fires operating, as it were, as a team. But the article did note that the burning has been extreme and is linked to climate change.

For more on the connection between fire and climate, please see my earlier post.

A somewhat later article from The Guardian provides more detail, confirming that the intense fire activity began in June and continued into July. Areas of Alaska, Siberia, and Greenland are involved. All told, it is the worst fire season the region has had in 16 years–which is as far as the satellite record goes back. Before then, it’s hard to know how many wildfires there really were, as the arctic is sparsely settled. The Guardian also confirms that in some areas the peat is burning. Peat, as you may recall, is organic material that doesn’t rot because it is normally waterlogged and highly acidic. The material builds up over thousands of years and represents a major carbon sink. That this stuff is burning is very bad news.

Other articles have covered similar territory over the past few weeks. More recently, NASA has explained why it is using its resources to study arctic fires; among other consequences for ecological function and public health, burning tundra has the potential to dramatically increase climate change. There are two main, and interrelated, mechanisms.

First, and most obviously, burning that peat releases a lot of sequestered carbon. But the other problem is that burning away vegetation and soil exposes the underlying permafrost to warmth, and it starts to melt. Without that ice, the ground can slump badly, and, of more global consequence, the organic matter previously trapped in ice can rot, releasing methane–a very powerful greenhouse gas.

So, on to the next bit of recent bad news.

Melting Records

This summer has broken global heat records, so it’s not surprising that the Arctic sea melted back to its second-smallest extent on record. Now, it’s important to be clear that sea ice is different from land ice. When glaciers melt (and that’s happening, too, of course), the water runs into the ocean and raises sea level. Melting sea ice does not raise sea levels because it was in the sea already. Put some ice in a glass, pour in enough water so the ice can float, and mark the level of the water. Let the ice melt, and you’ll see the water level stays the same. The sea works the same way.

Melting sea ice causes other problems, of course. Most obviously, polar bears depend on sea ice for hunting, but there are other issues. What makes the Arctic ocean distinct from the Atlantic is not geographic separation, but rather the ice, which both provides unique habitat and alters water chemistry and circulation. Without the ice, the Arctic ecosystem will collapse and merge with that of the Atlantic.

For example, the ice forms a substrate on which micro-algae can grow, sequestering carbon. Various animals eat that algae, notably copepods–an important food source for marine mammals. Copepods who don’t get eaten eventually die and sink to the ocean floor, taking their carbon with them. The Altantic has its own micro-algae and its own copepods, of course, but Altantic copepods are smaller and don’t carry as much carbon down to the sea floor.

The important thing to remember is that without sea ice, we’ll have one less ocean than we’re used to. The impact of that will be far-ranging.

This year has not been decisive. We knew the ice was melting before, and a significant amount of ice remains. This year’s heat is simply a reminder of what’s coming.

Heat

July was the hottest July on record–and the hottest of any month on record–worldwide. Before that, June was the hottest June on record, globally. The hot weather is the direct cause of the aforementioned melting and the indirect cause of the extensive fires. The heat itself is not caused by climate change; it is climate change.

Implications

I’m not saying everything is awful or hopeless–I wrote about hope last week, and Spock is still right. This is simply the world we live in, the context of everything we do. This is why it’s important for us to vote, to advocate, to educate ourselves and each other, and to protest.

Because climate change is real, and it’s not going away until we make it go away.

 

 

 

 

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It’s *%@$ing Cold

Actually, no it isn’t, at least not where I am. I’ve just been outside and the air is definitely brisk, I’d want a coat if I stayed out long, but it’s not unpleasant and the day looks beautiful and bright. But it is noticeably colder than it was yesterday, and I understand almost all of the United States is in a cold snap right now.

Predictably, the Internet is chattering about a “polar vortex” again, as if the term simply meant an unusually severe cold snap. It doesn’t–the polar vortex is not a weather event but a current within the atmosphere. There is always a polar vortex; it is the southern boundary of the polar air mass. It’s basically another name for the familiar jet stream. Sometimes the jet stream is almost straight, a circle drawn around the northern part of the globe. Sometimes it is wavy, bringing cold air farther south in some places and warmer air further north in other places. Right now, the boundary between polar and non-polar air is extremely wavy, and it is colder in Texas than in Alaska. What this is, really, is a good old fashioned cold-snap, albeit one that extends unusually far south.

There are signs that this year the media may shift to “arctic outbreak” as their buzzword of choice.

The current cold-snap is a little different than last year’s, where the cause of the extremely wavy boundary was debatable but might have been related to melting sea-ice in the arctic. Right now, we’re looking at the effects of the former Super Typhoon Nuri, which formed in the Western Pacific, became one of the most powerful storms of the year, and then weakened and recurved, heading northeast. By the time it reached Alaska it had lost its tropical characteristics (meaning its structure and the way energy moves through the system were no longer hurricane-like) but retained much of its power. Last week, the air mass formerly known as Nuri was among the most powerful storms in the Bering Sea ever recorded. Pacific storms can and do interact with the jet stream, causing weather changes hundreds of miles away. In this case, Nuri caused the boundary to become extremely wavy, freezing Texas.

Probably, some climate skeptics are wondering about global warming about now, and while I haven’t seen it yet, I expect some deniers are going to advance this cold-snap as proof against climate change. In writing this post, I’m being preemptive.

Yes, cold weather can be a symptom of global warming. A warmer atmosphere is generally more active, more prone to extremes of all kinds. A destabilized, extremely wavy polar vortex specifically could well be more common now that the arctic ice is melting, and Nuri, like all tropical cyclones, has a link to to global warming through the rising temperature of ocean water. This year’s Western Pacific typhoon season has not been startlingly intense (except for the monstrous Super Typhoon Vonfong, which fortunately weakened before it hit anyone), but it has been stronger than average. The sea has also been exceptionally warm.

But there are a couple of other points worth bearing in mind:

  • It isn’t cold everywhere. Yes, the weather is unusually cold today in the eastern half of the United States, but there are other parts of the world and some of those parts are unusually warm. An unstable polar vortex doesn’t actually make the average temperature of the world drop, it just redistributes cold air. Last year, while the Eastern U.S. was freezing and questioning the existence of climate change, the same weather patterns were causing record-breaking heat in California, Alaska, and parts of Europe. The hot weather exacerbated the California drought and caused a dangerous avalanche in Alaska that completely cut off one town’s road access. For the people there, global warming was not in doubt.
  • Coldness is relative and we have been spoiled by warm weather in recent years. Although the current “arctic blast” may break some local temperature records, it feels a lot colder than it really is because we’ve gotten used to the new normal of warm temperatures. Much of what we saw last winter would have been quite normal twenty or forty years ago (yes, I did just cite the cartoon, XKCD, but the cartoon in question does cite its sources and its author is an actual scientist).
  • Global warming means cold weather is rare, not that it never gets cold anymore. Yes, there are going to be genuinely cold years going forward, probably including some record-breakers where the entire planet is colder than it has been since record-keeping began. The weather on Planet Earth is extremely variable, and that isn’t going to change. What we are seeing, and will continue to see, is that the cold snaps are fewer and less severe than the warm spells. On average, we’re going up. 

This year, we have been especially far up. May, June, August, and September each broke global heat records. I am not certain, from the wording of my sources, whether May, June, and August were each in turn the hottest month ever, or simply the hottest May, June, and August ever. In either case, the records were based on a global average, meaning that they included measurements from places experiencing Fall or Winter at the time. September was definitely the hottest of any month ever recorded. 2014 is likely to be the planet’s hottest year on record, cold snaps in the U.S. notwithstanding. This is a big deal.

Weather.com put the situation in startling perspective:

Earth hasn’t set a monthly record for cold since December 1916, but all monthly heat records have been set after 1997.