Thursday, December 27, 2012

Today's MODIS image from the Terra satellite showed some interesting features. The image below is from NASA's Land and Atmosphere Near real-time Capability for EOS (LANCE) Rapid Response website and overlayed in Google Earth. The image is center over Las Cruces and if you look close at the clouds you can see a wave-like pattern on the east side of the Franklin and Organ Mountains. These area called gravity waves and are formed when the wind flow above us is perturbed by either mountains or another air mass that has a different density. In our case I think it may be mainly from the effects of wind being perturbed by the terrain behind the cold front.
There were other areas with gravity waves in NM, namely east of the Sandias and the Guadalupe Mountains. The Sandia waves were spread apart more and I like to call them lee waves, since they form on the lee-side of mountains. In today's case the winds are blowing from the west toward the east. Sometime the atmosphere is dry and hard to see these gravity waves. In order to see them without thick clouds I use the infrared spectrum that is sensitive to water vapor.