Lester R. Brown
Chapter 3. Climate Change and the Energy Transition: Rising Temperature and Its Effects
We are entering a new era, one of rapid and often unpredictable climate change. In fact, the new climate norm is change. The 25 warmest years on record have come since 1980. And the 10 warmest years since global recordkeeping began in 1880 have come since 1996. 7
The warming is caused by the accumulation of heat-trapping “greenhouse” gases and other pollutants in the atmosphere. Of the greenhouse gases, CO2accounts for 63 percent of the recent warming trend, methane 18 percent, and nitrous oxide 6 percent, with several lesser gases accounting for the remaining 13 percent. Carbon dioxide comes mostly from electricity generation, heating, transportation, and industry. In contrast, human-caused methane and nitrous oxide emissions come largely from agriculture—methane from rice paddies and cattle and nitrous oxide from the use of nitrogenous fertilizer. 8
Atmospheric concentrations of CO2, the principal driver of climate change, have climbed from nearly 280 parts per million (ppm) when the Industrial Revolution began around 1760 to 386 ppm in 2008. The annual rise in atmospheric CO2 level, now one of the world’s most predictable environmental trends, results from emissions on a scale that is overwhelming nature’s capacity to absorb carbon. In 2008, some 7.9 billion tons of carbon were emitted from the burning of fossil fuels and 1.5 billion tons were emitted from deforestation, for a total of 9.4 billion tons. But since nature has been absorbing only about 5 billion tons per year in oceans, soils, and vegetation, the remainder stays in the atmosphere, pushing up CO2 levels. 9
Methane, a potent greenhouse gas, is produced when organic matter is broken down under anaerobic conditions, including the decomposition of plant material in bogs, organic materials in landfills, or forage in a cow’s stomach. Methane can also be released with the thawing of permafrost, the frozen ground underlying the tundra that covers nearly 9 million square miles in the northern latitudes. All together, Arctic soils contain more carbon than currently resides in the atmosphere, which is a worry considering that permafrost is now melting in Alaska, northern Canada, and Siberia, creating lakes and releasing methane. Once they get under way, permafrost melting, the release of methane and CO2, and a rising temperature create a self-reinforcing trend, what scientists call a “positive feedback loop.” The risk is that the release of a massive amount of methane into the atmosphere from melting permafrost could simply overwhelm efforts to stabilize climate. 10
Another unsettling development is the effect on climate of atmospheric brown clouds (ABCs) consisting of soot particles from burning coal, diesel fuel, or wood. These particles affect climate in three ways. First, by intercepting sunlight, they heat the upper atmosphere. Second, because they also reflect sunlight, they have a dimming effect, lowering the earth’s surface temperature. And third, if particles from these brown clouds are deposited on snow and ice, they darken the surface and accelerate melting. 11
These effects are of particular concern in India and China, where a large ABC over the Tibetan Plateau is contributing to the melting of high-altitude glaciers that supply the major rivers of Asia. Soot deposition causes earlier seasonal melting of mountain snow in ranges as different as the Himalayas of Asia and the Sierra Nevada of California, and it is also believed to be accelerating the melting of Arctic sea ice. Soot particles have even been found in snow in Antarctica, a region once thought to be pristine and untouched by pollution. 12
In contrast to CO2, which may remain in the atmosphere for a century or more, soot particles in these clouds are typically airborne for only a matter of weeks. Thus, once coal-fired power plants are closed or wood cooking stoves in villages are replaced with solar cookers, atmospheric soot disappears rapidly. 13
If we continue with business as usual, the projected rise in the earth’s average temperature of 1.1–6.4 degrees Celsius (2–11 degrees Fahrenheit) during this century seems all too possible. These projections are the latest from the Intergovernmental Panel on Climate Change (IPCC), the world body of more than 2,500 leading climate scientists that in 2007 released a consensus report affirming humanity’s role in climate change. Unfortunately, during the several years since the study was completed, both global CO2 emissions and atmospheric CO2 concentrations have exceeded those in the IPCC’s worst-case scenario. 14
With each passing year the chorus of urgency from the scientific community intensifies. Each new report indicates that we are running out of time. For instance, a landmark 2009 study by a team of scientists from the Massachusetts Institute of Technology concluded that the effects of climate change will be twice as severe as those they projected as recently as six years ago. Instead of a likely global temperature rise of 2.4 degrees Celsius, they now see a rise of 5.2 degrees. 15
Another report, this one prepared independently as a background document for the December 2009 international climate negotiations in Copenhagen, indicated that every effort should be made to hold the temperature rise to 2 degrees Celsius above pre-industrial levels. Beyond this, dangerous climate change is considered inevitable. To hold the temperature rise to 2 degrees, the scientists note that CO2 emissions should be reduced by 60–80 percent immediately, but since this is not possible, they note that, “To limit the extent of the overshoot, emissions should peak in the near future.” 16
The effects of rising temperature are pervasive. Higher temperatures diminish crop yields, melt the mountain glaciers that feed rivers, generate more-destructive storms, increase the severity of flooding, intensify drought, cause more-frequent and destructive wildfires, and alter ecosystems everywhere.
What we can anticipate with a warmer climate is more extreme weather events. The insurance industry is painfully aware of the relationship between higher temperatures and storm intensity. Soaring weather-related damage claims have brought a drop in earnings and a flurry of lowered credit ratings for insurance companies as well as the reinsurance companies that back them up. 17
Companies using historical records as a basis for calculating insurance rates for future storm damage are realizing that the past is no longer a reliable guide to the future. This is a challenge not only for the insurance industry but for all of us. We are altering the earth’s climate, setting in motion trends we do not always understand with consequences we cannot anticipate.
Crop-withering heat waves have lowered grain harvests in key food-producing regions in recent years. In 2002, record-high temperatures and drought-reduced grain harvests in India, the United States, and Canada dropped the world harvest 90 million tons, or 5 percent below consumption. The record-setting 2003 European heat wave contributed to a world harvest that again fell short of consumption by 90 million tons. Intense heat and drought in the U.S. Corn Belt in 2005 contributed to a world grain shortfall of 34 million tons. 18
Such intense heat waves also take a direct human toll. In 2003, the searing heat wave that broke temperature records across Europe claimed more than 52,000 lives in nine countries. Italy alone lost more than 18,000 people, while 14,800 died in France. More than 18 times as many people died in Europe in this 2003 heat wave as died during the terrorist attacks on the World Trade Center in 2001. 19
There has also been a dramatic increase in the land area affected by drought in recent decades. A team of scientists at the National Center for Atmospheric Research (NCAR) reports that the area experiencing very dry conditions expanded from less than 15 percent in the 1970s to roughly 30 percent by 2002. The scientists attribute part of the change to a rise in temperature and part to reduced precipitation, with high temperatures becoming progressively more important during the latter part of the period. Most of the drying was concentrated in Europe, Asia, Canada, western and southern Africa, and eastern Australia. 20
A 2009 report published by the U.S. National Academy of Sciences and led by Susan Solomon of the National Oceanic and Atmospheric Administration reinforces these findings. It concludes that if atmospheric CO2 climbs from 385 ppm to 450–600 ppm, the world will face irreversible dry-season rainfall reductions in several regions of the world. The study likened the conditions to those of the U.S. Dust Bowl era of the 1930s. 21
Researchers with the U.S. Department of Agriculture’s Forest Service, drawing on 85 years of fire and temperature records, projected that a 1.6-degree-Celsius rise in summer temperature could double the area of wildfires in the 11 western states. 22
The Pew Center on Global Climate Change sponsored an analysis of some 40 scientific studies that link rising temperature with changes in ecosystems. Among the many changes reported are spring arriving nearly two weeks earlier in the United States, tree swallows nesting nine days earlier than they did 40 years ago, and a northward shift of red fox habitat that has it encroaching on the Arctic fox’s range. Inuits have been surprised by the appearance of robins, a bird they have never seen before. Indeed, there is no word in Inuit for “robin.” 23
The National Wildlife Federation (NWF) reports that if temperatures continue to rise, by 2040 one out of five of the Pacific Northwest’s rivers will be too hot for salmon, steelhead, and trout. Paula Del Giudice, Director of NWF’s Northwest Natural Resource Center, notes that “global warming will add an enormous amount of pressure onto what’s left of the region’s prime cold-water fish habitat.” 24
Douglas Inkley, NWF senior science advisor and senior author of a report to The Wildlife Society, notes, “We face the prospect that the world of wildlife that we now know—and many of the places we have invested decades of work in conserving as refuges and habitats for wildlife—will cease to exist as we know them, unless we change this forecast.” 25
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