High Resolution Dynamics Limb Sounder observations of the gravity wave-driven elevated stratopause in 2006

Temperature observations during January and February 2006 from the High Resolution Dynamics Limb Sounder (HIRDLS), the Microwave Limb Sounder (MLS), and the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) satellite instruments are compared to illustrate the vertical range over which version 6 HIRDLS temperatures are scientifically useful. In order to determine the quality of HIRDLS temperatures in the middle atmosphere, we compare the height and temperature of the HIRDLS stratopause with MLS and SABER before, during, and after the 2006 major stratospheric sudden warming. Results show that HIRDLS observes the elevated stratopause at 78 km two days later than MLS and five days after SABER. We compare the geographical temperature structure of these data sets at 0.01 hPa during this period. Though HIRDLS temperatures are consistently 5–10 K lower in the mesosphere, this is the first study to show that the horizontal temperature distribution is in good spatial and temporal agreement with MLS and SABER up to ~80 km. Gravity wave momentum flux and planetary wave 1 amplitudes are derived from HIRDLS and shown to be in agreement with previous studies. We use HIRDLS to show a ~30 K increase in stratopause temperature following enhanced gravity wave momentum flux in the lower mesosphere.