By Roland Piquepaille
It's now commonly admitted that our appetite for fossil fuels is having a strong influence on the Earth's climate -- and our future. But what about the concentration of humans in urban areas? Today, 50% of the world's population is living on about one percent of Earth's surface. Can this extreme concentration lead to other effects on our climate and weather? In 'Satellites and the city,' NASA says that it can help to provide an answer. "Our research suggests that, using satellite data and enhanced models, we will be able to answer several critical questions about how urbanization may impact climate change 10, 25 or even 100 years from now," says for example a NASA scientist from the Goddard Space Flight Center. But read more..."More and more people live in cities. This means that cities will grow rapidly over the next several decades. Evidence continues to mount that cities affect the climate," said J. Marshall Shepherd, Deputy Project Scientist of the Global Precipitation Measurement Mission at NASA's Goddard Space Flight Center, Greenbelt, Md.
Shepherd and co-author Menglin Jin, a research scientist at the University of Maryland-College Park, suggest that satellite-observed urban information is extremely useful for advancing our ability to simulate urban effects in climate models. They go on further to propose that satellite data is the only feasible way to represent the expanse of global urban surfaces and related changes to the Earth's surface, vegetation and aerosols.
Below are some images taken by the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite (Credit for images and legends: NASA).
This shows the MODIS land cover classification in southeastern US (near Atlanta). Red color is for Urban Land Build-up (Copied from Jin and Shepherd 2005 with original image source from Michael King).
[And here you can see] the global distribution of fine aerosol optical thickness derived from MODIS measurements on the Terra platform for September 2000. The large values over Southeast Asia, India, Europe, and the United States reflect urban pollution. The large values in the Southern Hemisphere are due to biomass burning.
The two scientists think that urban landscapes are changing the physical processes of land surfaces, such as thermal conductivity, and also adding new characteristics to our land and our atmosphere.
Structures like the Empire State Building in New York City can change the basic wind flow in and around cities that can alter air quality, temperature, cloud distribution and precipitation patterns. It is increasingly evident that such atmospheric changes near cities can be captured by NASA satellites such as Aqua, Landsat, Terra, and the Tropical Rainfall Measurement Mission (TRMM).
This research work has been published by the Bulletin of the American Meteorological Society in May 2005 (Vol. 86, No. 5, pp. 681
Famous quotes containing the words satellites, show, urban, effects and/or climate:
“To the Japanese, Portugal and Russia are neutral enemies, England and America are belligerent enemies, and Germany and her satellites are friendly enemies. They draw very fine distinctions.”
—Jerome Cady, U.S. screenwriter, and Lewis Milestone. Peter Voroshevski (Howard Clinton?)
“Population, when unchecked, increases in a geometrical ratio. Subsistence increases only in an arithmetical ratio. A slight acquaintance with numbers will show the immensity of the first power in comparison of the second.”
—Thomas Robert Malthus (1766–1834)
“And New York is the most beautiful city in the world? It is not far from it. No urban night is like the night there.... Squares after squares of flame, set up and cut into the aether. Here is our poetry, for we have pulled down the stars to our will.”
—Ezra Pound (1885–1972)
“Upon the whole, necessity is something, that exists in the mind, not in objects; nor is it possible for us ever to form the most distant idea of it, consider’d as a quality in bodies. Either we have no idea of necessity, or necessity is nothing but that determination of thought to pass from cause to effects and effects to causes, according to their experienc’d union.”
—David Hume (1711–1776)
“A tree is beautiful, but what’s more, it has a right to life; like water, the sun and the stars, it is essential. Life on earth is inconceivable without trees. Forests create climate, climate influences peoples’ character, and so on and so forth. There can be neither civilization nor happiness if forests crash down under the axe, if the climate is harsh and severe, if people are also harsh and severe.... What a terrible future!”
—Anton Pavlovich Chekhov (1860–1904)