Daily Earth Temperatures from Satellites
Please move the cursor to the altitude scale along the left side and click
the graphic to view the global atmospheric
temperature trend for the selected layer in the atmosphere, or choose a layer
in the atmosphere from the pulldown menu at the bottom left.
Daily averaged temperatures of the Earth are measured by the
AMSU flying on the NASA's Aqua satellite. The satellite passes over most points on
the Earth twice per day. The AMSU measures the average temperature of the atmosphere
in different layers from the surface up to about 135,000 feet or 41 kilometers. During
global warming, the atmosphere in the lower atmosphere (called the troposphere) is
supposed to warm at least as fast as the surface warms, while the statosphere above
the troposphere is supposed to cool much faster than the surface warms.
the graphs, you need to download the latest version of Java from
What is a brightness temperature? A brightness temperature is a descriptive
measure of radiation in terms of the temperature of a hypothetical blackbody
emitting an identical amount of radiation at the same wavelength.
The brightness temperature is obtained by applying the inverse of the
Planck function to the measured radiation. Depending on the nature of the
source of radiation and any subsequent absorption, the brightness temperature
may be independent of, or highly dependent on, the wavelength of the radiation.
A more technical description can be found in the Wikipedia article.
The global-average data displayed on this page have only limited quality
control, can undergo unannounced changes, and so should only be used as a
general guide. Official, quality-controlled global lower-tropospheric
temperatures, using more extensive processing procedures (and possibly
different satellite instruments) are updated every month and are available
from the Global Hydrology Resource Center.