Recent divergences in stratospheric water vapor measurements by frost point hygrometers and the Aura Microwave Limb Sounder. Public Deposited
  • Balloon-borne frost point hygrometers (FPs) and the Aura Microwave Limb Sounder (MLS) provide high-quality vertical profile measurements of water vapor in the upper troposphere and lower stratosphere (UTLS). A previous comparison of stratospheric water vapor measurements by FPs and MLS over three sites - Boulder, Colorado (40.0° N); Hilo, Hawaii (19.7° N); and Lauder, New Zealand (45.0° S) - from August 2004 through December 2012 not only demonstrated agreement better than 1% between 68 and 26 hPa but also exposed statistically significant biases of 2 to 10% at 83 and 100 hPa (Hurst et al., 2014). A simple linear regression analysis of the FP-MLS differences revealed no significant long-term drifts between the two instruments. Here we extend the drift comparison to mid-2015 and add two FP sites - Lindenberg, Germany (52.2° N), and San José, Costa Rica (10.0° N) - that employ FPs of different manufacture and calibration for their water vapor soundings. The extended comparison period reveals that stratospheric FP and MLS measurements over four of the five sites have diverged at rates of 0.03 to 0.07 ppmv year
Date Issued
  • 2016-09-08
Academic Affiliation
Journal Title
Journal Issue/Number
  • 9.0
Journal Volume
  • 9.0
File Extent
  • 4447-4457
Last Modified
  • 2019-12-06
  • PubMed ID: 28966694
Resource Type
Rights Statement
  • 1867-1381