Climate Emergency Institute
Climate Science Library
The Great Calling of Our Time
Max Wilbert, USA
Original Post: Jan. 2, 2012
It’s September in the high Arctic, the end of the brief summer season. Dozens of species of migratory birds, whales, and fish have gathered here in the land of eternal sun, raising their young and building up strength for the long return journey. The days are getting shorter, but the sunlight still glitters across the ice and snow for long hours every day. And on the edges of the sea ice, slowly but with gathering speed, the ice is melting, drop by drop.
Sea ice melts and refreezes in a natural cycle each year. Late every summer Arctic sea ice reaches its minimum extent in September, then begins to refreeze and expand as the short autumn ends and the long, fierce winter sets in again. But the past decade has seen sea ice shrink to record low levels, often only to be surpassed by the following year – 2011was the second lowest on record after 2007. Scientists have measured the recent melt at around 11% per decade.
Scientists believe that this unprecedented melting is being caused primarily by global warming – the process of heat being trapped on planet Earth, largely because of fossil fuels and logging. The carbon dioxide, methane, and other “greenhouse gases” released by this industrial activity is contributing to a long term warming trend in the planet’s atmosphere – and leading to melting glaciers, icecaps, and sea ice around the world.
This melting poses unique problems for indigenous people and the wildlife of the area - we’ve all heard about polar bears stranded far from shore and indigenous people unable to reach their hunting grounds as ice weakens and breaks up. But what if they are not the only ones being affected by this melting? What if, unbeknownst to all of us, this melt is affecting us every single day?
According to Dr. R. Max Holmes, an arctic researcher at Woods Hole Research Center, this curious process has global implications. Holmes says that sea ice keeps itself cool by reflecting incoming sunlight back towards space. But as the bright white ice melts, it reveals the ocean beneath – a much darker surface that absorbs energy from the sun much more easily.
Imagine wearing a white t-shirt on a hot summer day, then changing into a black one – you bake, right? This is the same idea, on a scale hard to fathom.
The process is called the ice-albedo feedback, Holmes explains. The warming ocean, absorbing a greater proportion of solar energy, contributes to further melting the sea ice from below, which allows more energy to be absorbed and accelerates the process of melting ice and warming water. This is a positive feedback loop – one of several in the arctic that scientists are concerned about.
On land, a similar process is taking place as glaciers and seasonal snow cover is melting and revealing darker rock, soil, and vegetation beneath. These positive feedbacks (along with several others) are the reason warming in the Arctic regions is proceeding more than twice as fast as the global average – some regions have warmed even faster, averaging more than 5° F warmer in recent years than 50 years ago. This is called the Arctic Amplification – a well-studied process that is having ramifications around the world.
According to research published in 2010 in the Journal of Geophysical Research by Sergey Petoukhov and Vladimir Semenov, reductions in wintertime ice cover may be having a big effect on European weather patterns. As wintertime ice recedes in the seas north of Russia, their research shows that the warmer surface of the ocean warms the lower atmosphere and triggers a high pressure zone as this warmer air rises. This high pressure zone pulls warmer air masses out of continental Europe, triggering an average decline of nearly 3° F in the region’s wintertime weather.
Global warming leading to snowier winters? Not as far fetched as one might imagine. Semenov and Petoukhov write, “Recent severe winters do not conflict the global warming picture but rather supplement it.”
Other research echoes these findings, showing that warmer but wetter winters are likely across much of the northern hemisphere, such as the exceptional snows of winter 2010/2011 in the northeastern and north-central United States. New research shows that these snowy winters in much of the United States may be due to a disruption to the polar vortex caused by declining wintertime sea ice cover, which allows cold arctic air masses to escape southward, leading to the “warm Arctic-cold continent” phenomenon.
Another possible effect of sea ice melt is even more dramatic. As sea ice freezes, it rejects salt and increases the salinity, and therefore density, of the waters beneath. These saline waters sink, flow along the bottom of the ocean, and power strong currents that carry huge masses of water, support abundant fish and wildlife populations, and moderate global climate. Scandinavia and the United Kingdom are one example – the region is kept substantially warmer by this “thermohaline circulation.” But climate models show that the influx of fresh water from melting sea ice could shut down this circulation and plunge the region into a much colder weather regime.
Summertime effects of sea ice loss are just as striking, if not more so. Higher temperatures across the northern hemisphere are leading to extreme weather, increased mortality, crop failures, droughts, floods, insect outbreaks, the spread of disease, and powerful storms. Recent years have seen the northern hemisphere slammed by repeated extreme events.
In 2003, Europe was hit with its worst heat wave on record, after crops had already suffered a harsh winter. Sixty percent of fodder for livestock was lost, along with sizable chunks of the grain, grape, and potato crops. More than 46,000 deaths were attributed to the unusual heat.
Russia was next in line: in 2010, record high temperatures swept the country. Twelve percent of the cultivated land was lost and more than 56,000 people died from pollution, drowning, heat stress, and thousands of wildfires across the country. The devastation was so total that the formerly denial Russian Academy of Sciences changed its tune.
This heat wave set records around the world, and covered more than twice as much land surface as the 2003 event. Sixteen other countries set all time heat records. Food prices jumped around the world and triggered unrest in dozens of countries around the world, including Sudan, Jordan, Tunisia, and Algeria. These rising prices may have contributed to instability that led to the “Arab Spring” – a string of revolutions across the Middle East and North Africa that is yet to be finished.
The 2011 drought in China also contributed to rising food prices. It was the worst drought to hit China in 50 years. More than 34 million people were affected before the drought ended. This drought affects a region in the north of China that is the major wheat-growing region of the country, an area that has been experiencing declines in rainfall for 30 years that are attributed to the changing climate.
This is just a small sampling of the dire climatic changes occurring across the northern hemisphere and the world. But the worst is yet to come. Projections show that, on our current emissions path, what are now extreme temperatures (like the 2003 heat wave in Europe or 2010 in Russia) will be “the new normal” across the grain belt – the region which grows the bulk of the global food supply. This alone could lead to yield reductions of between 2% and 16% on grain crops, according to 2009 research published in Science magazine by David Battistiof the University of Washington and Rosamond Naylor of Stanford University.
Europe and the United States will also have to cope with reductions of more than 20% in their water supply by the 2060’s, compared to the 1961-1990 average, according to the latest climate simulations. Some regions, like the Mediterranean and the Southwestern US will be particularly hard hit – these areas can expect sustained drought conditions worse than the dustbowl of the 1930’s.
Scientists, military researchers, and insurance companies have issued warnings that these food shortages, coupled with deficits in energy, fresh water, and other basic resources are likely to lead to increasing political instability and inter-state conflict, unless emissions are reduced substantially and over a short timescale. The sooner the better – global temperature lags several decades behind gas emissions – the warming is not instant – so we are now only experiencing the consequences of greenhouse gas levels in the 80’s and 90’s.
All of this is frightening enough on its own, but the bad news keeps on rising like flood waters. In 2010, researchers including Karen Shell, Prof. of Atmospheric Science at Oregon State University decided to do direct measurements of the decline in albedo in the Arctic. Their research, which was published in Nature Geoscience in early 2011 shows that the magnitude of the albedo loss from melting snow and ice may be more than double what was used for climate modeling up to this point. Shell says this new data shows that the recent decline in albedo may responsible for an amount of warming equivalent to an 8% increase in overall atmospheric greenhouse gas concentrations – equivalent to jumping from 400 parts per million of carbon dioxide to 432.
These dramatic conclusions continue the trajectory of climate science in general: conservative estimates being superseded by accelerating planet-wide destruction. Emissions are tracking at the high end of scenarios considered by climate modelers. Forests continue to fall around the world, and fossil fuels continue to be burned. As Arctic sea ice melts, governments and transnational corporations are salivating over natural gas, oil, methane hydrates, mineral resources that are revealed, and newly ice-free trade routes that are becoming accessible for the first time. Leave it to them to find a way to profit from this.
Scientists are clear on one thing – if we cut emissions drastically and soon, we can still control this process. According to the Copenhagen Diagnosis, a November 2009 synthesis of the climate science up to that point, emissions need to peak between 2015 and 2020 and be cut by between 80-95% by 2050 to have a good chance of avoiding 3.5° F rise in temperature globally. This is what scientists consider the upper limit of “safe” warming – beyond that, the chance of crossing thresholds and tipping points in the climate system rise rapidly. But given their track record of underestimating the rate of warming and the scope of its consequences, can we afford even that? Is the high-energy way of life we have built worth these risks? We have a responsibility to address these problems – in our personal lives, and in our communities. It is the great calling of our time, and it will take seriousness, sacrifice, and organization.
"A thing is right when it tends to preserve the integrity, stability, and beauty of the biotic community. It is wrong when it tends otherwise." - Aldo Leopold, A Sand County Almanac
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