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Many algorithms have been developed to retrieve precipitation and cloud liquid water from passive microwave measurement at mid-latitudes and in the tropics, but these algorithms do not necessarily work well over the ice-free oceans that surround the Antarctic continent where most precipitation falls in the form of snow.It is known that the clouds that produce most of the precipitation over the southern latitudes are thin stratiform clouds and the precipitation they give is of slight intensity (less than 0.5mm h -1 rain equivalent). In this paper the polarization corrected temperature (PCT) method for detecting precipitation is applied and compared with a new physical method that simultaneously retrieves both cloud liquid water and precipitation amount. Both methods are compared with the few in situ measurements available. The new iterative physical method is found to give better results and does not need any empirically derived parameters. read more
Read Full Story Paying up to 40% more for organic food is worth the investment, wrote Chensheng (Alex) Lu, associate professor of environmental exposure biology at Harvard School of Public Health (HSPH), in a Wall Street Journal article on June 16, 2013.While researchers have yet to provide a definitive answer about whether more costly and harder-to-find organic food, such as produce, milk, and meat, is healthier than conventional foods, “It only makes sense that food free of pesticides and chemicals is safer and better for us than food containing those substances, even at trace levels,” Lu wrote.What’s more, he wrote, “Some convincing scientific does exist to suggest that an organic diet has its benefits.” In 2006 Lu led a study published in Environmental Health Perspectives that showed that within five days of substituting mostly organic produce for conventional produce in children’s diets, pesticides disappeared from the children’s urine.Both Lu and a University of Florida physician, who countered Lu’s view on buying organic, advised those on limited budgets to consider buying organic versions of foods on the Environmental Working Group’s “Dirty Dozen” list, or focus on organic versions of foods eaten most frequently. Eating more fruits, vegetables, and whole grains and less processed foods remains the goal, they wrote. read more