Beaufort Sea This MODIS Terra image, captured July 25, 2006, shows the Beaufort Sea, a large body of water which is actually part of the Arctic Ocean. Located north of the Northwest Territories, the Yukon, and Alaska and west of Canadaâ€™s Arctic islands, its northwestern boundary is defined by a line connecting Point Barrow, Alaska, and Lands End, Prince Patrick Island. It is about 450,000 square km in area. The entire Beaufort Sea is totally frozen during much of the year. The permanent icepack covers the northern edge of it year-round. The sea is named after British hydrographer Sir Francis Beaufort.
Phytoplankton Bloom Off The Coast Of Ireland June 2, 2006, the MODIS on the Aqua satellite captured this unique image of a phytoplankton bloom off the coast of Ireland. Swirls of phytoplankton, microscopic plants that grow in sunlit ocean surface waters, color the ocean brilliant blues and greens. The ocean normally appears black in true-color, photo-like satellite imagery. England appears to the east of Ireland. Towards the south of England, there appear to be smaller phytoplankton blooms near the coastline!
Betsiboka Estuary This MODIS image shows the Betsiboka Estuary, located on the northwest coast of Madagascar. Over the last century, a great deal of Madagascarâ€™s rainforests and coastal mangroves have been cleared, resulting in increased erosion of the land. After heavy rains, the bright red soil is washed from the hillsides into the streams and rivers. As a result, this estuary, which is the mouth of Madagascarâ€™s largest river, appears bright red.
Flooding in Iceland Most spring floods are triggered by rain or melting snow, but when the Skafta River of southern Iceland flooded in late April 2006, geologic activity may have been the driver. The river flows out from under the Vatnajokull Ice Cap, a large permanent field of snow and ice that covers more than 8,000 square kilometers of southeastern Iceland, including a number of volcanoes and other regions of geothermal activity. Over these hotspots, the lower layer of the ice cap melts to form glacier lakes, some of which drain into the Atlantic Ocean through rivers such as the Skafta. Other lakes are dammed by walls of ice from the overlying glacier. Catastrophic floods can occur when water breaks through the ice dams and bursts into the rivers, or when geologic activity increases and melts more water.
Western Russia Snow and ice cover the land surface in this image of western Russia acquired on February 19, 2006. Snow and ice (on the land) are key components of the cryosphere, which also includes sea ice, freshwater ice, glaciers, frozen ground and permafrost. Objects on the Earthâ€™s surface that are white, such as ice and snow crystals have a high albedo, which means that they reflect most of the sunlight that they receive. Fresh snow has an albedo somewhere in the range of 75â€“95%, as compared to the rest of the Earth which averages about 30%. The net result of this is that snow and ice produce a cooling effect and changes to the cryosphere, such as reductions in the amount of glaciers, could contribute to or amplify global warming trends.
Dust Storm in Egypt A massive dust storm obscures the Nile River Valley and Delta in this image acquired on February 8, 2006. Westerly winds are kicking up dust, perhaps from the Qattara Depression (just below and to the left of the approximate center of the image), one of the largest sources of dust on the planet. A series of dry lakebeds are located to the west and northwest of the depression and appear as brown patches. According to Andy Ballantine from the University of California, Santa Barbaraâ€™s Institute for Computational Earth System Science, the lakebeds in the Qattara Depression, or possibly fine-grained deposits near them, are the likely source of the dust storm; the most concentrated part of the plume seems to be the northern part which would agree with the pattern of lakebeds (assuming they
Cloud Streets Along The Alaska Peninsula The striking patterns visible in this image are called “cloud streets”. Cloud streets are a regular feature of the middle and high latitudes; these are located along the Alaska Peninsula, just south of Anchorage. Cloud streets form when cold air blows across the landscape and passes over warmer water. The cold air picks up energy from the warm water and rises (a process called “convection”) vertically. At the same time, the now-warmer air is being pushed horizontally by air currents. These competing forces produce vortices, pockets or masses of swirling air that resemble a tornado on its side. However, not all of the pockets are spin in the same direction; in fact, adjacent vortices spin in opposite directions. But they are all aligned in the direction of the prevailing winds, creating the linear patterns seen
Thick Smog Over China Skies over China have darkened in the past five decades, thanks to a nine-fold increase fossil-fuel emissions. Yun Qian and collaborators examined data from over 500 weather stations, finding a reduction overcast days and an increase in cloud-free days. In January 2006, they reported these results in the journal Geophysical Research Letters. According to the Associated Press, Qian stated that pollution (mainly soot and sulfur) reduces sunlight, allowing less of it to reach Chinaâ€™s urban areas. The Moderate Resolution Imaging Spectroradiometer (MODIS) flying onboard the Aqua satellite captured this image on January 27, 2006. In this image, a thick plume of smog makes its way across the Yellow Sea towards Korea. To the east, cloud cover can be discerned by its bright white appearance, compared to
Dust Storm off Egypt A large, swirling mass of dust, visible on the top left portion of the image, is blowing from the Sahara into the Mediterranean Sea. The country on the left is Libya, while the Nile Delta of Egypt is clearly recognizable on the right side of the image. Dust storms occur when very strong winds carry sand from the erg, or sand dune deserts, of the Sahara. They are a naturally occurring phenomenon and may â€œfertilizeâ€? the oceans and even the Amazon rain forest by carrying and depositing minerals over great distances. However, dust storms are often exacerbated by agriculture practices that contribute to soil erosion- a process called desertification. Projects are currently underway to remedy this problem by creating barriers to block to movement of sand and by planting vegetation to keep sand in place.
Northern Siberia Sea ice breaks up and drifts away into the Laptev Sea in this true-color Terra MODIS image of northern Siberia from July 1, 2005. Summer temperatures are finally reaching the northernmost climates, causing thick sea ice to break up as the land blooms into the rich green of vegetation. This part of Siberia is sparsely populated - most of Russiaâ€™s Siberian population lives in cities farther south and west - yet rich in natural beauty and mineral wealth. The bright red dots in the image are locations where MODIS detected active fire signatures, and indeed some of them are producing smoke plumes that stream away to the northwest. In this image, Lena River flows north along the left side of the image, while the Verkhoyanskiy and Cherskogo mountains cradle smaller Yana River.
Hydrogen Sulphide Eruptions Along The Coast Of Namibia These eruptions happen because the Benguela Current pulls rich nutrients from the cold ocean floor to the warmer ocean surface where large colonies of phytoplankton thrive. They consume the nutrients, and when they die they sink back to the ocean floor where bacteria in the mud decompose their remains, producing hydrogen sulfide gas as a byproduct. As this gas rises toward the surface, it interacts with oxygen in the water to produce white clouds of pure sulfur. The white sulfur and deep blue ocean water combine into these milky turquoise-colored blooms.
Cloud Vortex Streets Off The Cape Verde Islands Low-level winds rushing over the Cape Verde Islands off the coast of northwestern Africa created cloud vortex streets, as seen in this true-color Terra MODIS image from January 5, 2005. The vortex streets tend to create patterns of swirls and curves in a roughly symmetrical pattern, though as can be seen here, the lower vortex street is much more disorganized - to the point that the typical features are almost unrecognizeable. Cloud vortices are also known as von Karman vortices.
Icebergs In The Ross Sea, Antarctica As winter deepens its hold across the Northern Hemisphere, summer shows its face in the Southern Hemisphere. At the southernmost extreme is Antarctica, which even at its most balmy is covered in ice and painted in shades of black and white. In the center of the scene are a number of large icebergs, including the huge B-15A iceberg, which calved off the Ross Ice Shelf in 2000. Trapped between the huge 窶話erg and the Ice Shelf are a number of smaller icebergs and sea ice. Over the scene, light clouds stream across the open water and land. This true-color Terra MODIS image was acquired on January 11, 2005.