In the soil moisture map (top), the streak of blue that stretches from the lower Mississippi Valley through Maine is evidence of weather systems that moved through the area during the last week, dropping rain and snow in some areas. However, the groundwater map (bottom) shows that these storms have done little to replenish parched aquifers.
The deep drought in the United States that has fueled wildfires, damaged crops and caused near record-low water levels on the Mississippi River has lingered well into January.
Though there has been some relief from a series of recent winter storms, a pair of satellites operated by NASA shows that groundwater supplies continue to be unusually low in many parts of the country.
The accompanying maps combine data from the twin satellites of the Gravity Recovery and Climate Experiment (GRACE) with other satellite and ground-based measurements to model the relative amount of water stored near the surface and underground between Jan. 8“Jan. 14, 2013. The top map shows moisture content in the top 2 centimeters (0.8 inches) of surface soil; the bottom map shows the condition of groundwater in aquifers. The soil moisture map depicts short-term conditions, while the groundwater map offers a longer-term perspective.
The wetness, or water content, of each layer is compared with the average between 1948 and 2009. Groundwater levels remain at low levels in many parts of the country.
Image courtesy of NASA.
