1 Average Clear-sky Net Radiant Flux The Earth's climate is determined by energy transfer from the sun to the Earth's land, oceans, and atmosphere. As the Earth rotates, the sun lights up only part of the Earth at a time, and some of that incoming solar energy is reflected and some is absorbed, depending on type of area it lights. The average amount of reflection and absorption is critical to the climate, because the absorbed energy heats up the Earth until it is radiated away as thermal radiation. This animation shows the monthly clear-sky average net radiant flux from July, 2002 through June, 2004 as measured by the CERES instrument. This is the incoming radiation minus the outgoing reflected or thermal energy given off by areas of the Earth when the sky is cloud-free. Regions in red and yellow have a net incoming flux and are being heated. Regions in blue have a net outgoing flux and are being cooled. Regions in black are in rough equilibrium. Summertime oceans are heated the most, while high latitude winter regions are cooled the most, probably because of the longer winter nights. Note that the Earth's ice sheets are almost always regions of cooling. On average, the heating and cooling amounts must balance, or the Earth will change temperature and the climate will change. Animation (144x72) This animation shows the monthly average clear-sky net radiant flux from CERES for July 2002 through June 2004. 1 0 2002-07-01 2004-07-01 2002-07 1 1 2002-07-01 2002-08-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0000.png -90 90 -180 180 2002-08 1 1 2002-08-01 2002-09-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0001.png -90 90 -180 180 2002-09 1 1 2002-09-01 2002-10-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0002.png -90 90 -180 180 2002-10 1 1 2002-10-01 2002-11-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0003.png -90 90 -180 180 2002-11 1 1 2002-11-01 2002-12-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0004.png -90 90 -180 180 2002-12 1 1 2002-12-01 2003-01-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0005.png -90 90 -180 180 2003-01 1 1 2003-01-01 2003-02-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0006.png -90 90 -180 180 2003-02 1 1 2003-02-01 2003-03-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0007.png -90 90 -180 180 2003-03 1 1 2003-03-01 2003-04-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0008.png -90 90 -180 180 2003-04 1 1 2003-04-01 2003-05-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0009.png -90 90 -180 180 2003-05 1 1 2003-05-01 2003-06-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0010.png -90 90 -180 180 2003-06 1 1 2003-06-01 2003-07-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0011.png -90 90 -180 180 2003-07 1 1 2003-07-01 2003-08-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0012.png -90 90 -180 180 2003-08 1 1 2003-08-01 2003-09-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0013.png -90 90 -180 180 2003-09 1 1 2003-09-01 2003-10-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0014.png -90 90 -180 180 2003-10 1 1 2003-10-01 2003-11-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0015.png -90 90 -180 180 2003-11 1 1 2003-11-01 2003-12-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0016.png -90 90 -180 180 2003-12 1 1 2003-12-01 2004-01-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0017.png -90 90 -180 180 2004-01 1 1 2004-01-01 2004-02-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0018.png -90 90 -180 180 2004-02 1 1 2004-02-01 2004-03-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0019.png -90 90 -180 180 2004-03 1 1 2004-03-01 2004-04-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0020.png -90 90 -180 180 2004-04 1 1 2004-04-01 2004-05-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0021.png -90 90 -180 180 2004-05 1 1 2004-05-01 2004-06-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0022.png -90 90 -180 180 2004-06 1 1 2004-06-01 2004-07-01 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/frames/144x72/netflcls.0023.png -90 90 -180 180 Legend 1 3 http://svs.gsfc.nasa.gov/vis/a000000/a003000/a003093/netflclsbar.0000.png