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Snow Cover & Net Radiation

Global Map Snow Cover Image 1 Global Map Snow Cover Image 2 Global Map Snow Cover Image 3 Global Map Snow Cover Image 4 Global Map Snow Cover Image 5 Global Map Snow Cover Image 6 Global Map Snow Cover Image 7 Global Map Snow Cover Image 8 Global Map Snow Cover Image 9 Global Map Snow Cover Image 10 Global Map Snow Cover Image 11 Global Map Snow Cover Image 12 Global Map Snow Cover Image 13 Global Map Snow Cover Image 14 Global Map Snow Cover Image 15 Global Map Snow Cover Image 16 Global Map Snow Cover Image 17 Global Map Snow Cover Image 18 Global Map Snow Cover Image 19 Global Map Snow Cover Image 20 Global Map Snow Cover Image 21 Global Map Snow Cover Image 22 Global Map Snow Cover Image 23 Global Map Snow Cover Image 24 Global Map Snow Cover Image 25 Global Map Snow Cover Image 26 Global Map Snow Cover Image 27 Global Map Snow Cover Image 28 Global Map Snow Cover Image 29 Global Map Snow Cover Image 30 Global Map Snow Cover Image 31 Global Map Snow Cover Image 32 Global Map Snow Cover Image 33 Global Map Snow Cover Image 34 Global Map Snow Cover Image 35 Global Map Snow Cover Image 36 Global Map Snow Cover Image 37 Global Map Snow Cover Image 38 Global Map Snow Cover Image 39 Global Map Snow Cover Image 40 Global Map Snow Cover Image 41 Global Map Snow Cover Image 42 Global Map Snow Cover Image 43 Global Map Snow Cover Image 44 Global Map Snow Cover Image 45 Global Map Snow Cover Image 46 Global Map Snow Cover Image 47 Global Map Snow Cover Image 48 Global Map Snow Cover Image 49 Global Map Snow Cover Image 50 Global Map Snow Cover Image 51 Global Map Snow Cover Image 52 Global Map Snow Cover Image 53 Global Map Snow Cover Image 54 Global Map Snow Cover Image 55 Global Map Snow Cover Image 56 Global Map Snow Cover Image 57 Global Map Snow Cover Image 58 Global Map Snow Cover Image 59 Global Map Snow Cover Image 60 Global Map Snow Cover Image 61 Global Map Snow Cover Image 62 Global Map Snow Cover Image 63 Global Map Snow Cover Image 64 Global Map Snow Cover Image 65 Global Map Snow Cover Image 66 Global Map Snow Cover Image 67 Global Map Snow Cover Image 68 Global Map Snow Cover Image 69 Global Map Snow Cover Image 70 Global Map Snow Cover Image 71 Global Map Snow Cover Image 72 Global Map Snow Cover Image 73 Global Map Snow Cover Image 74 Global Map Snow Cover Image 75 Global Map Snow Cover Image 76 Global Map Snow Cover Image 77 Global Map Snow Cover Image 78 Global Map Snow Cover Image 79 Global Map Snow Cover Image 80 Global Map Snow Cover Image 81 Global Map Snow Cover Image 82 Global Map Snow Cover Image 83 Global Map Snow Cover Image 84 Global Map Snow Cover Image 85 Global Map Snow Cover Image 86 Global Map Snow Cover Image 87 Global Map Snow Cover Image 88 Global Map Snow Cover Image 89 Global Map Snow Cover Image 90 Global Map Snow Cover Image 91 Global Map Snow Cover Image 92 Global Map Snow Cover Image 93 Global Map Snow Cover Image 94 Global Map Snow Cover Image 95 Global Map Snow Cover Image 96 Global Map Snow Cover Image 97 Global Map Snow Cover Image 98 Global Map Snow Cover Image 99 Global Map Snow Cover Image 100 Global Map Snow Cover Image 101 Global Map Snow Cover Image 102 Global Map Snow Cover Image 103 Global Map Snow Cover Image 104 Global Map Snow Cover Image 105 Global Map Snow Cover Image 106 Global Map Snow Cover Image 107 Global Map Snow Cover Image 108 Global Map Snow Cover Image 109 Global Map Snow Cover Image 110 Global Map Snow Cover Image 111 Global Map Snow Cover Image 112 Global Map Snow Cover Image 113 Global Map Snow Cover Image 114 Global Map Snow Cover Image 115 Global Map Snow Cover Image 116 Global Map Snow Cover Image 117 Global Map Snow Cover Image 118 Global Map Snow Cover Image 119 Global Map Snow Cover Image 120 Global Map Snow Cover Image 121 Global Map Snow Cover Image 122 Global Map Snow Cover Image 123 Global Map Snow Cover Image 124 Global Map Snow Cover Image 125 Global Map Snow Cover Image 126 Global Map Snow Cover Image 127 Global Map Snow Cover Image 128 Global Map Snow Cover Image 129 Global Map Snow Cover Image 130 Global Map Snow Cover Image 131 Global Map Snow Cover Image 132 Global Map Snow Cover Image 133 Global Map Snow Cover Image 134 Global Map Snow Cover Image 135 Global Map Snow Cover Image 136 Global Map Snow Cover Image 137 Global Map Snow Cover Image 138 Global Map Snow Cover Image 139 Global Map Snow Cover Image 140 Global Map Snow Cover Image 141 Global Map Snow Cover Image 142
Snow Cover
Snow Cover Scale
Net Radiation
Net Radiation Scale
Global Map Net Radiation Image 1 Global Map Net Radiation Image 2 Global Map Net Radiation Image 3 Global Map Net Radiation Image 4 Global Map Net Radiation Image 5 Global Map Net Radiation Image 6 Global Map Net Radiation Image 7 Global Map Net Radiation Image 8 Global Map Net Radiation Image 9 Global Map Net Radiation Image 10 Global Map Net Radiation Image 11 Global Map Net Radiation Image 12 Global Map Net Radiation Image 13 Global Map Net Radiation Image 14 Global Map Net Radiation Image 15 Global Map Net Radiation Image 16 Global Map Net Radiation Image 17 Global Map Net Radiation Image 18 Global Map Net Radiation Image 19 Global Map Net Radiation Image 20 Global Map Net Radiation Image 21 Global Map Net Radiation Image 22 Global Map Net Radiation Image 23 Global Map Net Radiation Image 24 Global Map Net Radiation Image 25 Global Map Net Radiation Image 26 Global Map Net Radiation Image 27 Global Map Net Radiation Image 28 Global Map Net Radiation Image 29 Global Map Net Radiation Image 30 Global Map Net Radiation Image 31 Global Map Net Radiation Image 32 Global Map Net Radiation Image 33 Global Map Net Radiation Image 34 Global Map Net Radiation Image 35 Global Map Net Radiation Image 36 Global Map Net Radiation Image 37 Global Map Net Radiation Image 38 Global Map Net Radiation Image 39 Global Map Net Radiation Image 40 Global Map Net Radiation Image 41 Global Map Net Radiation Image 42 Global Map Net Radiation Image 43 Global Map Net Radiation Image 44 Global Map Net Radiation Image 45 Global Map Net Radiation Image 46 Global Map Net Radiation Image 47 Global Map Net Radiation Image 48 Global Map Net Radiation Image 49 Global Map Net Radiation Image 50 Global Map Net Radiation Image 51 Global Map Net Radiation Image 52 Global Map Net Radiation Image 53 Global Map Net Radiation Image 54 Global Map Net Radiation Image 55 Global Map Net Radiation Image 56 Global Map Net Radiation Image 57 Global Map Net Radiation Image 58 Global Map Net Radiation Image 59 Global Map Net Radiation Image 60 Global Map Net Radiation Image 61 Global Map Net Radiation Image 62 Global Map Net Radiation Image 63 Global Map Net Radiation Image 64 Global Map Net Radiation Image 65 Global Map Net Radiation Image 66 Global Map Net Radiation Image 67 Global Map Net Radiation Image 68 Global Map Net Radiation Image 69 Global Map Net Radiation Image 70 Global Map Net Radiation Image 71 Global Map Net Radiation Image 72 Global Map Net Radiation Image 73 Global Map Net Radiation Image 74 Global Map Net Radiation Image 75 Global Map Net Radiation Image 76 Global Map Net Radiation Image 77 Global Map Net Radiation Image 78 Global Map Net Radiation Image 79 Global Map Net Radiation Image 80 Global Map Net Radiation Image 81 Global Map Net Radiation Image 82 Global Map Net Radiation Image 83 Global Map Net Radiation Image 84 Global Map Net Radiation Image 85 Global Map Net Radiation Image 86 Global Map Net Radiation Image 87 Global Map Net Radiation Image 88 Global Map Net Radiation Image 89 Global Map Net Radiation Image 90 Global Map Net Radiation Image 91 Global Map Net Radiation Image 92 Global Map Net Radiation Image 93 Global Map Net Radiation Image 94 Global Map Net Radiation Image 95 Global Map Net Radiation Image 96 Global Map Net Radiation Image 97 Global Map Net Radiation Image 98 Global Map Net Radiation Image 99 Global Map Net Radiation Image 100 Global Map Net Radiation Image 101 Global Map Net Radiation Image 102 Global Map Net Radiation Image 103 Global Map Net Radiation Image 104 Global Map Net Radiation Image 105 Global Map Net Radiation Image 106 Global Map Net Radiation Image 107 Global Map Net Radiation Image 108 Global Map Net Radiation Image 109 Global Map Net Radiation Image 110 Global Map Net Radiation Image 111 Global Map Net Radiation Image 112 Global Map Net Radiation Image 113 Global Map Net Radiation Image 114 Global Map Net Radiation Image 115 Global Map Net Radiation Image 116 Global Map Net Radiation Image 117 Global Map Net Radiation Image 118 Global Map Net Radiation Image 119 Global Map Net Radiation Image 120 Global Map Net Radiation Image 121 Global Map Net Radiation Image 122 Global Map Net Radiation Image 123 Global Map Net Radiation Image 124 Global Map Net Radiation Image 125 Global Map Net Radiation Image 126 Global Map Net Radiation Image 127 Global Map Net Radiation Image 128 Global Map Net Radiation Image 129 Global Map Net Radiation Image 130 Global Map Net Radiation Image 131 Global Map Net Radiation Image 132 Global Map Net Radiation Image 133 Global Map Net Radiation Image 134 Global Map Net Radiation Image 135 Global Map Net Radiation Image 136 Global Map Net Radiation Image 137 Global Map Net Radiation Image 138 Global Map Net Radiation Image 139 Global Map Net Radiation Image 140 Global Map Net Radiation Image 141 Global Map Net Radiation Image 142

Earth's climate, including its average surface temperature, depends on the balance between incoming and outgoing energy. Energy comes in to the system when sunlight penetrates the top of the atmosphere. Energy goes out in two ways: reflection by clouds, aerosols, or the Earth's surface; and thermal radiation — heat emitted by the surface and the atmosphere, including clouds. The balance between incoming and outgoing energy is called net flux. Snow on the ground can dramatically change Earth's net flux by increasing the amount of sunlight the ground reflects.

The snow cover map shows the fraction of an area covered by snow on a monthly basis. Measurements were made by the MODIS sensor on NASA’s Terra satellite. Gray indicates land areas with no snow, darkest blue represents minimal snow cover, and solid white indicates 100 percent snow cover. Because MODIS relies on visible light to assess snow cover, the sensor cannot collect data over the highest latitudes of the Northern Hemisphere during winter when no sunlight reaches the polar region.

The map of net flux shows monthly changes in the balance of incoming and outgoing energy on Earth as measured by the Clouds and the Earth Radiant Energy System (CERES) sensor on NASA's Terra and Aqua satellites. Places where the amounts of incoming and outgoing energy were in balance are white. Places where more energy was coming in than going out (energy surplus) are orange. Places where less energy was coming in than going out (energy deficit) are purple.

The most obvious pattern in both maps is the way they both change with the seasons. The comparison starts in late summer in the Northern Hemisphere. As the September equinox approaches, a zone of positive net flux (more energy coming in than going out) is nearly centered over the equator. As the season changes into winter, Northern Hemisphere snow cover increases. Meanwhile, the zone of positive net flux shifts to the Southern Hemisphere , and a swath of negative net flux (more energy going out than coming in) appears in the high latitudes of the Northern Hemisphere. The pattern reverses on the March equinox.

The influence of snow cover on net flux is most clearly demonstrated in areas of permanent snow cover: Greenland and Antarctica. Snow is so reflective that even on the December and June solstices — when alternate hemispheres are receiving the maximum amount of direct sunlight they will receive all year — the net flux of these permanently snow-covered places is still zero or slightly negative. In December, the Southern Ocean surrounding Antarctica has an energy surplus (red): it is absorbing more energy from incoming sunlight than it is reflecting or emitting as heat. But Antarctica itself remains yellow, which means that incoming and outgoing energy are in balance. This balance is possible because the snowy surface reflects so much more incoming sunlight than the dark blue waters of the ice-free ocean. A similar pattern appears over Greenland in June, when the surrounding area is red (energy surplus) while Greenland itself is yellow-green (slightly negative net flux).

View, download, or analyze more of these data from NASA Earth Observations (NEO):
Snow Cover
Net Radiation