A "stocking rate" reflects how many animals a designated area of acreage will support. The unpredictability of precipitation causes difficulty for Great Plains ranchers to estimate this rate. Scientists developed a new computer model to assist by extrapolating National Weather Service seasonal weather predictions. A revised computer model tests various scenarios for forage yields and the weight gains of livestock under varied weather conditions. Ranchers will now be able to better estimate if precipitation will likely be above or below normal for a given season. This model also determines the effects of increased carbon dioxide and higher temperature on pasture forage. In closing, and after Wednesday morning's record low, medical experts report that high temperatures in certain regions of the country are often correlated with low urine volume that ultimately leads to dehydration. Another consequence of rising global temperatures is the increased risk of kidney stone formation.  The University of Texas at Dallas and The University of Texas Southwestern Medical Center advanced research related to kidney stones. They predict that approximately 2.2 new climate-related cases of kidney stones will occur by 2050.  The belt of elevated risk of kidney stones extends from Florida to Texas and California.  The first research team matched models of predicted temperature increases based on future increases in greenhouse gases. Continued climate warming could expand the belt northward and westward.