Instrumental and ice core records show that several components of the atmosphere and surface have significant changes in the recorded climate history. First, the concentration of greenhouse gases such as carbon dioxide has increased dramatically since 1850, causing an increase in the atmospheric absorption of outgoing radiation and warming the atmosphere. Aerosols, microscopic droplets or airborne particles, have also increased, and these have reflected and absorbed incoming solar radiation.
The most obvious change in the short-term climate is the increase in temperature of the atmosphere and sea surface. The period between 1995 and 2006 ranks among the hottest on record since instrumental records have been in widespread use since 1850, containing 11 of the 12 hottest years recorded. Moreover, the rate of temperature rise has increased each decade since 1850. The total temperature increase since 1850 is estimated by the IPCC to be 1.4°F (0.76°C). Measurements of the atmospheric water vapor indicate it is increasing with increasing temperature of the atmosphere, although such measurements extend back only to the mid-1980s.
sea level has been rising at about 0.07 inches per year (0.18 cm/yr) since 1961, and at 0.12 inches per year (0.31 cm/yr) since 1993. The temperature of the oceans to a depth of 1.9 miles (3 km) has been increasing since at least 1961, with seawater absorbing most (~ 80 percent) of the heat energy associated with global warming. This increase in seawater tem perature is causing the water to expand, contributing to sea-level rise. Also contributing to sea-level rise is a dramatic melting of mountain glaciers in both the
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