Ah, Alaska—that great Northern state of expansive wilderness, rugged mountains, frozen tundra, breathtaking glaciers and… 96 degree temperatures? No, that last item was not a mistake. Earlier this week, the state of Alaska broke its all-time high temperature record twice, hitting a high of 91 degrees F on Sunday, and then immediately smashing that record with a high of 96 degrees F on Monday. It is very important to recognize the distinction between weather (short term and temporary) and climate (long-term trends). However, when I see something like this, it is hard not to wonder whether we’re beginning to see the “global weirding” that climate scientists and advocates have been warning us about for decades: those increasingly frequent strange weather events that leave Alaska residents desperately wishing for air conditioning, while folks in California are wearing sweaters. Those moments that leave us scratching our heads and thinking “wait… something doesn’t seem right here”. Alaska will return to more normal temperatures once they get out from underneath the high pressure system that has currently taken up residence in the region, and that is certainly a good thing. Although (thankfully) we aren’t at this point yet, the recent hot weather in Alaska got me to thinking about the serious trouble we’d be in if indeed 96 degree temperatures became the norm for the Arctic. Everyone knows that melting of the Arctic is not a good thing, but many people don’t realize that this situation holds more serious consequences than the much-publicized plight of the polar bears. This little-known threat in the Arctic goes by a familiar name: methane.
June 19th, 2013 map of temperature variation showing that the state of Alaska is much
warmer than anywhere else on the continent. Source: Climate Central
Methane? Yep, the very same gas responsible for flatulence is also a greenhouse gas that poses a serious threat to our climate. As bacteria ferment or break down organic matter, they produce methane as a byproduct. In the Arctic, much of the land has been frozen for eons beneath glaciers or in permafrost, which has essentially “frozen” the fermentation process and created a “methane sink” that prevented this greenhouse gas from being released into the atmosphere. As our planet warms and the Arctic begins to thaw, those little bacteria will get back to work breaking down organic matter and releasing significant amounts of methane. Scientists fear that melting of glaciers and permafrost will release a devastating amount of methane into the atmosphere – a great “methane belch” that will further accelerate the warming of our planet and push the process of climate change beyond the point where anything can be done to mitigate it.
So what makes methane so dangerous? Molecule-for-molecule, methane has a heat-trapping capacity that is approximately 20 times greater than its more famous partner in crime, carbon dioxide. This means that methane in the atmosphere is trapping 20 times more heat from the sun than the same amount of carbon dioxide. However, the good news about methane is the fact that its lifespan in the atmosphere is relatively short-lived. One molecule of methane will last for 12 years in the atmosphere, while one molecule of carbon dioxide will last for as long as 50-200 years. For this reason, organizations such as 1250now.org are advocating for a focus on methane reductions as an effective short-term strategy for combating climate change, complementary to the long-term need for carbon dioxide reductions. They argue that in fact, reaching the much-touted “safe” target of 350 parts per million of atmospheric carbon dioxide will not be possible unless steps are taken to address methane emissions as well. Their goal is to push for an atmospheric methane level of no greater than 1250 parts per billion to avoid potentially devastating climate change effects and further melting of the Arctic. (The differences between the two target numbers for carbon dioxide and methane are very revealing as to their potential danger in regard to warming the climate: when converted into the same units, 350ppm of carbon dioxide is considered safe, but only 1.25ppm – 1250ppb - is considered safe for methane)
Below is a table from the EPA detailing the largest sources of methane emissions in the United States. As you can see, human activities are responsible for a large percentage of the methane emissions in the US. These are the areas that need to be adjusted, regulated, and re-designed to minimize methane emissions and hinder the climate-warming effects of this potent greenhouse gas.
US Methane Emissions, by Source
Although carbon dioxide will continue to warm our climate for centuries to come due to its long lifespan in the atmosphere, in the short term, there is increasing evidence that we can make a meaningful impact on the trajectory of climate change if we can control methane emissions. Unfortunately, there is nothing that we can directly do to control methane being released from the melting Arctic, other than doing our best to control emissions of the greenhouse gases that warm the planet and contribute to that melting to begin with. Groups such as 350.org and 1250now.org are fighting to do just that. Let us hope that in the decades and centuries to come, we can still look upon Alaska as a state known for its stunning wilderness, rather than a state known as the one that melted.