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CoreLogic® Finds More Than $234 Billion in Residential Storm Surge Exposure in 13 U.S. Cities

Climate Change Is Beginning to Disrupt Agriculture

Climate variability has already affected rains, droughts and temperatures in several parts of the United States, said Cynthia Rosenzweig, a senior research scientist with NASA's Goddard Institute for Space Studies. "We are already seeing climate change." "We are seeing the expansion of drying," said Rosenzweig, as she brought up a slide showing precipitation measurements across the United States. The measurements, comparing values from 1958 through 2008, showed significant reductions in rainfall across large portions of the Northwest and Southeast. Idaho, Washington, Montana, Georgia and Florida had some of the most drastic changes in rainfall on the map. However, the opposite is not good either, she said, adding that increased soil moisture in some areas could potentially harbor insects and other pests. And, in general, "crops do not like to have their feet wet." Aside from concerns about rainfall, local temperature is also extremely important for crop performance. The reproductive development in many important grains is a process sensitive to temperature, said Paul Gepts, a professor of agronomy at the University of California, Davis. Some plants need cold winters One of the potential side effects of climate change is a trend toward milder winters in some regions. Vital plants, Gepts said, require a cold winter in order to properly develop their seeds for the next season. Rosenzweig agreed. Heat waves, at odd times of the year, affect the proper development of proteins within corn kernels, she said. "It is like scrambling eggs." Gepts also presented a number of well-known strategies for mitigating some of the possible economic effects of climate change on agriculture. Aside from breeding plants to be more drought-, heat- and pest-resistant, he also suggested varying the types of crops maintained on a particular site on the basis of environmental suitability.

In an ominous sign of climate change hitting home, India has seen accelerated warming in the past few decades and the temperature-rise pattern is now increasingly in line with global warming trends. The most up-to-date study of temperatures in India, from 1901 to 2007, has found that while it’s getting warmer across regions and seasons, night temperatures have been rising significantly in almost all parts of the country. The rise in night temperatures — 0.2 degrees Celsius per decade since 1970, according to the study — could have potentially adverse impact on yields of cereal crops like rice. The paper also finds that warming has been highest in post-monsoon and winter months (October to February).

‘‘Until the late 1980s, minimum (or night) temperatures were trendless in India. India was an odd dot in the global map as most regions worldwide were seeing a rise in night temperatures in sync with growing levels of greenhouse gases. Our analysis shows the global trend has caught up with India,’’ said K Krishna Kumar, senior scientist and programme manager at Indian Institute of Tropical Meteorology, Pune, and one of the authors.

The rising night temperatures are a major cause of worry. Said Jagdish K Ladha, principal scientist in the India chapter of International Rice Research Institute, ‘‘Minimum temperatures have a link with rice fertility. At higher than normal night temperatures, rice grains aren’t properly filled up, leading to a drop in yield.’’

The new report shows that over 80% of the whitebark pine forests of Wyoming, Idaho, and Montana are already dead or dying.

“The red and grey trees littering the western landscape are a testament to the fact that North America’s forests are under assault,” said Louisa Willcox, senior wildlife advocate for NRDC and one of the minds behind a new report on whitebark pine mortality in the Greater Yellowstone Ecosystem. “Climate change is hitting the whitebark pine hard by allowing mountain pine beetles access to previously inhospitable forests at higher elevations.  Whitebark, which grows from roughly 8500 feet up to treeline, has never had to fight off a threat like this, and if we don’t act quickly, we could lose this essential tree species.”

Unfortunately for those dependent wildlife species, such as squirrels, chipmunks, grosbeaks, crossbills, and grizzlies (especially in Yellowstone) as well as other creatures, whitebark pine forests are being decimated throughout their range by an array of threats that have emerged in high-elevation environments, as a result of climate change, particularly now swarming mountain pine beetles, as well as an invasive nonnative disease, blister rust.

Severe and persistent drought held southern Russia in its grip in June and July 2010. Low rainfall and hot temperatures damaged 32 percent of the country’s grain crops, said Russian Agriculture Minister, Yelena Skrynnik on July 23. This satellite vegetation index image, made from data collected by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite, shows the damage done to plants throughout southern Russia. A previously published image of land surface temperatures shows extreme heat in the drought region at the same time. The vegetation index is a reflection of photosynthesis. The index is high in areas where plants are dense, with plenty of photosynthesizing leaves. The index is low when plants are thin or not present. This image is a vegetation index anomaly image that compares photosynthesis between June 26 and July 11, 2010, to average conditions observed in late June and early July between 2000 and 2009. Below-average plant growth is shown in brown, while average growth is cream-colored. If there had been above-average growth in the region, it would have been represented in green. The land around the Volga River is brown in this image. Plants throughout the region were stressed, producing fewer leaves and photosynthesizing less between June 26 and July 11, 2010. The image is speckled brown. In the large image, which covers a broader region in more detail than the web image, the dots are clearly fields of crops. Here, the dots blend together to reveal a broad region of drought-affected crops. The Volga region is one of Russia’s primary spring wheat-growing areas. The vegetation index values shown here were the lowest late-June values seen in Russia’s spring wheat zone since the MODIS sensor began taking measurements in 2000, said an analyst from the United States Department of Agriculture (USDA) Foreign Agricultural Service. Largely as a result of the drought, the USDA expected Russia’s overall wheat crop to be 14 percent smaller than in 2009. The drought affects more than Russian farmers. Russia is the world’s fourth largest wheat exporter. If Russia isn’t able to supply as much wheat, the world’s overall wheat supply will drop. With less wheat on the market, wheat prices will go up. As of July 23, wheat futures (the current price for wheat that will be harvested and delivered in September) had risen for four consecutive weeks because of the expected drop in supply of Russian wheat, reported Bloomberg.

As she did for winter 2010, this summer Mother Nature has truly outdone herself, this time by brewing up a miserable combination of heat and humidity that has enveloped not only the northeastern U.S., but much of the Northern Hemisphere as well. As Ian Livingston reported on Saturday, July was the warmest single calendar month of all time in Washington (tied with July 1993). The warmest day in the city was July 7th, when the temperature soared to 102 degrees Fahrenheit at Reagan National Airport. The day before, the temperature rose to a sweltering 105 F at Baltimore-Washington International Airport. In total, Washingtonians sweated through 21 July days during which temperatures exceeded 90 degrees. Baltimore set a new record for the average daily high temperature, which was 92.5 degrees, beating July 1988's 91.9 degrees. New York City and Philadelphia experienced their second-warmest months since records began in the late 1800s. New York recorded an average monthly temperature of 81.3 degrees, which was 4.8 degrees above the July average. The warmest July on record there occurred in 1999, when the average temperature was 81.4 degrees.

Although long-term global climate change doesn't directly cause a particular heat wave, the pronounced warming trend in global average temperatures during the past century has increased the odds of more frequent and severe heat waves. For example, scientists have partially attributed the deadly 2003 European heat wave, which killed tens of thousands, to manmade climate change.

By collating and analyzing about half a million Secchi observations, plus other direct measurements of algae, the Dalhousie team estimated that phytoplankton levels declined by about 1% of the global average each year from 1899 onward. The data are more reliable for recent decades, translating into a 40% decline in algae since 1950.

The team investigated several factors that could have caused the decline, including wind intensity, cyclical climate changes and sea-surface temperature. "We found that temperature had the best power to explain the changes," said Boris Worm, a marine biologist at Dalhousie and co-author of the study.

Mike Behrenfeld, an expert on phytoplankton who has read the Nature paper, said it was similar to a 1992 study which also used Secchi data to show a long-term decline in marine algae in the north Pacific. "But this paper covers the globe," said Dr. Behrenfeld of Oregon State University. "And the scientists also took the next step of relating the [algal decline] to sea temperatures."