Inconvenient truths
Another eventful year
From thawing permafrost to trouble for the polar bear, we are one more year closer to a warmer world. Or are we? The year 2011 brought us face to face with many troublesome truths.
1. Kyoto concerns: The 2011 conference, held in Durban, South Africa, ran from November 28 to December 11. Delegates from about 200 nations gathered together to try to advance the world’s response to intensifying climate disasters. One of the issues still left unresolved was the future of the Kyoto Protocol, the 1997 agreement that requires major industrialised nations to meet targets on emissions reduction but imposes no mandates on developing countries, including emerging economic powers and sources of global greenhouse gas emissions like China, India, Brazil and South Africa.
The United States is not a party to the protocol, having refused to even consider ratifying it because of those asymmetrical obligations. Expectations for the meeting were low, and it ended with modest accomplishments: the promise to work toward a new global treaty in coming years and the establishment of a new climate fund.
2. Weather extremes: At least some of the weather extremes being seen around the world are consequences of human-induced climate change and can be expected to worsen in coming decades, a United Nations panel reported in November.
That weather-related catastrophes cause a lot of destruction is well known. But the prospect that increasing floods, droughts and storms will prompt many millions of people to migrate to safer areas is still poorly understood and anticipated, according to a report from the Asian Development Bank. The study was released in early March.
3. Grin and bear it: A study released in February offered an ominous forecast for one flagship Arctic species, the polar bear. Bears in some parts of the far north are under increasing stress because of climate change. These bears do most of their feeding during the winter as they venture onto the sea ice to catch seals. But with the ongoing decline of that ice in recent decades, life has gotten harder for many of the bears.
4. Shrinking times: Climate change’s laundry list of impacts — melting glaciers and rising sea levels, shifts in timing for bird migration and flower budding, a poleward shift of species — just got a new addition: shrinking species. No, not population sizes, but a diminution in the size of the animals by comparison with the pre-global warming days. Judging from the fossil record, creatures like beetles, spiders and pocket gophers shrank during periods of warming in the past like the Paleocene-Eocene Thermal Maximum about 55.8 million years ago, the researchers write.
5. Dying forests: The pines of the northern and central Rockies in the US are dying, just one among many types of forests that are showing signs of distress these days. The devastation extends worldwide. The great euphorbia trees of southern Africa are succumbing to heat and water stress. So are the Atlas cedars of northern Algeria. Fires fed by hot, dry weather are killing enormous stretches of Siberian forest.
Eucalyptus trees are succumbing on a large scale to a heat blast in Australia, and the Amazon recently suffered two “once a century” droughts just five years apart, killing many large trees. Scientists have figured out — with the precise numbers deduced only recently — that forests have been absorbing more than a quarter of the carbon dioxide that people are putting into the air by burning fossil fuels and other activities.
6. Species movement: Scientists from the University of York examined the movement of 2,000 animal and plant species over the past decade. According to their study, published in Science in September, in their exodus from increasing heat, species have moved, on average, 13.3 yards higher in altitude — twice the predicted rate — and 11 miles higher in latitude — three times faster than expected. These changes have happened most rapidly where the climate has warmed the most.
7. More trouble for reefs: Nearly three-quarters of the planet’s reefs are now at risk of serious degradation, according to a report by the World Resources Institute in February. Another analysis, by the Global Coral Reef Monitoring Network, found that as much as one-fifth of the world’s reefs have been degraded beyond recognition or lost entirely. By midcentury, virtually all reefs will be at risk, scientists fear, not just from local threats or global warming, but from an increasingly acidified ocean.
8. Sixth mass extinction: For decades, scientists have warned that humans may be ushering in a sixth mass extinction. In April, a group of scientists at the University of California, Berkeley, applied new statistical methods to a new generation of fossil databases. If endangered species continue to disappear, we will indeed experience a sixth extinction, over just the next few centuries or millennia.
9. Warm waters: Water flowing from the North Atlantic into the Arctic Ocean is warmer today than at any time in the past 2,000 years, a January 2011 study shows. The waters of the Fram Strait, which runs between Greenland and the Arctic archipelago of Svalbard, have warmed roughly 3.5 degrees Fahrenheit over the past 100 years, the study’s authors said.
10. Permafrost: A recent estimate suggests that the perennially frozen ground known as permafrost, which underlies nearly a quarter of the Northern Hemisphere, contains twice as much carbon as the entire atmosphere. Temperatures are warming across much of that region, primarily, scientists believe, because of the rapid human release of greenhouse gases.
Permafrost is warming, too. Some has already thawed, and other signs are emerging that the frozen carbon may be becoming unstable.
