Hey, it's cooler near the sprinklers.Extensive agricultural irrigation irrigation, in agriculture, artificial watering of the land. Although used chiefly in regions with annual rainfall of less than 20 in. (51 cm), it is also used in wetter areas to grow certain crops, e.g., rice. can significantly affect local climate and may be masking the effects of global warming
The predicted effects of global warming on the environment and for human life are numerous and varied. It is generally difficult to attribute specific natural phenomena to long-term causes, but some effects of in some areas, a new study suggests. In arid and semiarid semiarid said of regions of the earth which have dry climates but not as dry as those of arid climates. regions, irrigation enables farmers to grow crops that wouldn't naturally thrive. But adding large volumes of water to normally dry ground changes the climate in many ways, says Lara M. Kueppers, an ecosystem scientist at the University of California, Merced Organization and governance UC Merced is headed by a chancellor. The position was held by Carol Tomlinson-Keasey from 1999 until she resigned on August 31, 2006. She returned to teaching and research in psychology in 2007. . For example, irrigation typically darkens the soil, which then absorbs more heat. The resulting increase in evaporation cools the air and boosts humidity, she notes. Kueppers and her colleagues used computer models to estimate the climatic effects of irrigation in California, where farmers provide extra water to around one-twelfth of the state's land. One set of simulations depicted modern land use, and another set simulated only natural vegetation. During a simulated 20-year period, August daytime-high temperatures at irrigated sites were on average 7.5[degrees]C lower than they would have been if they'd been covered with natural vegetation, says Kueppers. In those irrigation-cooled areas, humidity increased an average of 25 percentage points. Applied to California as a whole, these results imply that irrigation keeps the average August temperature about 0.38[degrees]C lower than it would otherwise he. That's about the same amount of greenhouse gas-triggered warming that some climate models suggest will occur in coming decades, the researchers note in the Feb. 16 Geophysical Research Letters Geophysical Research Letters is a publication of the American Geophysical Union. GRL is the organization's only letters journal. Since its introduction in 1974, GRL has published only short research letters, typically 3-5 pages long, which focus on a specific discipline or . If the extent of irrigated farmland declines in the future because of water shortages or urban sprawl, irrigations evaporative cooling Evaporative cooling is a physical phenomenon in which evaporation of a liquid, typically into surrounding air, cools an object or a liquid in contact with it. Latent heat describes the amount of heat that is needed to evaporate the liquid; this heat comes from the liquid itself and effect probably will decrease as well.--S.P. |
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