NASA's SMAP Mission Captures the Land/Ocean Response to 2017 Hurricanes

Friday, November 16, 2018

Evolution of the SMAP sea surface salinity (SSS) and soil moisture responses to Hurricanes Harvey, Irma, and Maria of 2017. The ocean salinity response to hurricanes is a combination of two competing effects: 1) salinity freshening due to enhanced precipitation and 2) salinity increase due to wind stress-generated vertical mixing, wherein increased salinity from a mid-level maximum (found in typical salinity profiles) is brought to the surface. The two effects are clearly observed along the tracks of Harvey, Irma, and Maria. Salinity freshening due to precipitation can be seen along the hurricane tracks, whereas increased salinity from wind stress-generated vertical mixing is observed to the right of the hurricane tracks, especially Irma and Maria. Hurricane Harvey provides a nice example of the land-ocean response, wherein increased precipitation led to elevated soil moisture levels in Texas that drained into the adjacent Gulf of Mexico post-storm decreasing coastal salinity. [SMAP SSS: 10.5067/SMP40-3TPCS].