Efforts to Control Global Warming

    Responding to the challenge of controlling global warming will require fundamental changes in energy production, transportation, industry, government policies, and development strategies around the world. These changes take time. The challenge today is managing the impacts that cannot be avoided while taking steps to prevent more severe impacts in the future.     Reducing emissions of greenhouse gases, also called greenhouse...

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Effects of Global Warming: Human Health

In a warmer world, scientists predict that more people will get sick or die from heat stress, due not only to hotter days but more importantly to warmer nights (giving the sufferers less relief). More frequent and intense heat waves will further contribute to this trend.  At the same time, there will be some decreases in the number of cold-related deaths. Diseases such as malaria, now found in the tropics and transmitted...

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Effects of Global Warming: Agriculture, Plants and Animals

    AGRICULTURE    Global warming of a few degrees may increase agricultural production, but not necessarily in the same places where crops are grown now. Southern Canada, for example, may benefit from more rainfall and a longer growing season. At the same time, the semiarid tropical farmlands in some parts of Africa may become further impoverished. Farming regions such as California’s Central Valley that...

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Effects of Global Warming: Ice Sheets and Glaciers

Arctic Ice Cover in 1979 and 2005 Surface temperatures in the Arctic have risen almost twice as much as the global average. Satellites have made continual observations of Arctic sea ice since 1978. The extent of Arctic sea ice has declined by about 8.5 percent per decade from its size in 1979 (top image). Since 2002 satellite records have revealed unusually early onsets of springtime melting in the areas north of Alaska and Siberia, as well...

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Effects of Global Warming: Sea Level

Arctic Ice Cover in 1979 and 2005 Surface temperatures in the Arctic have risen almost twice as much as the global average. Satellites have made continual observations of Arctic sea ice since 1978. The extent of Arctic sea ice has declined by about 8.5 percent per decade from its size in 1979 (top image). Since 2002 satellite records have revealed unusually early onsets of springtime melting in the areas north of Alaska and Siberia, as well...

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Effects of Global Warming: Weather

Storm Surge Barrier, The Netherlands Some experts predict that an increase in global warming will result in unpredictable weather patterns, including storm surges in which wind piles up water in low-lying areas. The curved arms of the New Waterway Storm Surge Barrier in The Netherlands protect Rotterdam and other inland cities from flooding during large storms on the North Sea. Normally, the large, curved arms are retracted to allow ships from...

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Effects of Global Warming

  Scientists use elaborate computer models of temperature, precipitation patterns, and atmosphere circulation to study global warming. Based on these models, scientists have made many projections about how global warming will affect weather, glacial ice, sea levels, agriculture, wildlife, and human health. Many changes linked to rising temperatures are already being observed. Weather Ice Sheets and Glaciers Sea Level Agriculture Plants...

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Global Warming Projections

  In its 2007 report the IPCC projected temperature increases for several different scenarios, depending on the magnitude of future greenhouse gas emissions. For a “moderate” scenario—in which emissions grow slowly, peak around the year 2050, and then fall—the IPCC report projected further warming of 1.1 to 2.9 Celsius degrees (1.9 to 5.2 Fahrenheit degrees) by the year 2100. For a “high-emissions” scenario—in which emissions...

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Debates Over Global Warming

    While the behavior of the climate system and the processes that cause global warming are well understood and grounded in basic scientific principles, scientists are still working to understand certain details of the climate system and its response to increasing greenhouse gases. Scientific uncertainty is inevitable with a system as complex as Earth’s climate. However, advancements in measuring, analyzing, and modeling...

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Measuring Global Warming

GOES Weather Satellite Broadcasters use data from meteorological satellites to predict weather and to broadcast storm warnings when necessary. Satellites such as the Geostationary Operational Environmental Satellite (GOES) collect meteorological and infrared information about the atmosphere and the ocean. A camera on the GOES is continuously pointed at Earth, broadcasting satellite images of cloud patterns both day and night. Here, the GOES-C...

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Greenhouse Gases: Aerosols

    Fuel combustion, and to a lesser extent agricultural and industrial processes, produce not only gases but also tiny solid and liquid particles called aerosols that remain suspended in the atmosphere. Although aerosols are not considered greenhouse gases, they do affect global warming in several ways.    Diesel engines and some types of biomass burning produce black aerosols such as soot,...

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Greenhouse Gases: Synthetic Chemicals

   Manufacturing processes use or generate many synthetic chemicals that are powerful greenhouse gases. Although these gases are produced in relatively small quantities, they trap hundreds to thousands of times more heat in the atmosphere than an equal amount of carbon dioxide does. In addition, their chemical bonds make them exceptionally long-lived in the environment.      Human-made greenhouse gases include chlorofluorocarbons...

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Greenhouse Gases: Ozone

Smog in Los Angeles Ozone in the lower atmosphere is a component of smog, a severe type of air pollution. This low-altitude ozone is a greenhouse gas formed by nitrogen oxides and volatile organic gases emitted by automobiles and industrial sources. In contrast, the ozone in the upper atmosphere occurs naturally and forms the ozone layer, which shields life on Earth from the Sun’s harmful ultraviolet radiation.        ...

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Greenhouse Gases: Nitrous Oxide

             Nitrous oxide is a potent greenhouse gas that is released primarily by plowing farm soils and burning fossil fuels. Nitrous oxide traps about 300 times more heat than does the same amount of carbon dioxide. The concentration of nitrous oxide in the atmosphere has increased 18 percent over preindustrial levels. Nitrous oxide contributes about a tenth as much as carbon dioxide...

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Greenhouse Gases: Methane

Alaskan Tundra Global warming has been most dramatic in the Arctic, where temperatures have risen almost twice as much as the global average. The vast tundra (Arctic plains) of Alaska, Siberia, and other subpolar regions contains a layer of frozen subsoil called permafrost. The area of frozen ground has decreased due to rising temperatures, and scientists are concerned that as the permafrost melts it will release large amounts of methane, a potent...

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