Photo Gallery Graphic Evidence of Global Warming
This graph shows the increase in the concentration of carbon dioxide in the earth's atmosphere over the last 10,000 years (panel inset shows the increase since 1750) based on the study of ice cores. Different colors represent different studies. Radiative forcing indicates the influence a factor has on the amount of energy entering or leaving the earth's atmosphere and is an index of how important the factor is as a climate change mechanism. The higher it is, the more important it is.
This graph shows the increase in the concentration of methane in the earth's atmosphere over the last 10,000 years (panel inset shows the increase since 1750) based on the study of ice cores. Different colors represent different studies. Radiative forcing indicates the influence a factor has on the amount of energy entering or leaving the earth's atmosphere and is an index of how important the factor is as a climate change mechanism. The higher it is, the more important it is.
This graph shows the increase in the concentration of nitrous oxide in the earth's atmosphere over the last 10,000 years (panel inset shows the increase since 1750) based on the study of ice cores. Different colors represent different studies. Radiative forcing indicates the influence a factor has on the amount of energy entering or leaving the earth's atmosphere and is an index of how important the factor is as a climate change mechanism. The higher it is, the more important it is.
Changes in a) global average surface temperature; b) global average sea level rise; and c) snow coverage in the Northern Hemisphere from March to April. All changes are relative to corresponding averages for the period 1961 to 1990. Smoothed curves represent decadal averaged values while circles show yearly values.
A comparison of continental and global surface temperature rises. The black lines show decade-by-decade rises relative to the average from 1901 to 1950. The blue lines shows natural forces contributing to global warming. The pink lines show natural forces combined with human activity.
What next? The middle column shows projections for temperature increases based on three separate models. The middle column shows 2020-2029 and the right hand column shows 2090 to 2099. The color-coded scale corresponds to Celsius degree rises. The three scenarios B1, A1B and A2 are based on different assumptions about economic growth, population development and fuel usage.
This graph shows expected relative changes in winter precipitation (in percent) for the period 2090 to 2099 relative to the period 1980 to 1999 using the A1B model. White areas show where less than 66 percent of the models agree on the change. Dotted areas show where more than 90 percent of the models agree.
This graph shows expected relative changes in summer precipitation (in percent) for the period 2090 to 2099 relative to the period 1980 to 1999 using the A1B model. White areas show where less than 66 percent of the models agree on the change. Dotted areas show where more than 90 percent of the models agree.
How hot is it going to get? The black line at the left shows the 20th century. The colored solid lines show where the temperature might go using different models -- shading indicates error ranges. Bars at the right show best estimates (solid lines) with the gray showing the likely range.
