Conveners
UTLS Water Vapour
- Daan Hubert (BIRA-IASB)
UTLS Water Vapour
- Christian Rolf (Forschungszentrum Jülich)
Variations in water vapor and other constituents in the upper troposphere and lower stratosphere (UTLS) have important radiative and chemical impacts on climate. Here we use gridded data from Aura Microwave Limb Sounder (MLS) satellite observations and five meteorological and composition-focused reanalyses (ERA5, MERRA-2, JRA-3Q, M2-SCREAM, and CAMSRA) to evaluate reanalysis representations of...
We present trends in upper tropospheric humidity and ice saturation based on NOAA/HIRS brightness temperature measurements over the past 40 years (1979-2020). The analysis is based on data of upper tropospheric humidity with respect to ice (UTHi) derived from measurements in HIRS channels 12 and 6 (T12 and T6; water vapour channel and temperature channel, respectively) using the retrieval...
The four-wavelengths differential absorption lidar (DIAL) WALES has been operated onboard the research aircraft HALO over the past 15 years to measure water vapor (WV) profiles from the Arctic to the Tropics. Here, we present a study on the quantification of the lower-stratospheric moist bias in the ERA5 reanalysis using the multi-campaign WALES dataset. The applied 33000 mid-latitude profiles...
Lightning can be considered a signature of deep convection over the observed region. Such deep convective systems can transport significant water vapor to the upper troposphere and lower stratosphere (UTLS) region. We used the Icosahedral Nonhydrostatic Weather and Climate Model (ICON) in Climate Limited-area Mode (CLM) at the k-scale to investigate how lightning-associated deep convective...
Measuring water vapor concentration in the Upper Troposphere/Lower Stratosphere (UTLS) region presents significant challenges due to complex atmospheric conditions and low densities. The current study sheds light on several Raman lidar systems with promising capabilities for providing high-resolution and accurate water vapor profiles, namely: the IPRAL Raman lidar (25 km south of Paris) and...
The unique characteristics of the combined data set from MOZAIC and IAGOS (http://www.iagos.org) with its global-scale sampling on air traffic routes make it ideally suited for long-term characterizations in the extratropical UT, namely at mid-latitudes with the highest flight densities.
We will present trend analyses from 1996 to 2019 for absolute humidity, temperature, and relative...
Water vapor (H$_2$O) is a key trace gas in the upper troposphere (UT) and lowermost stratosphere (LMS), as it significantly influences the Earth's climate system through its roles in radiative forcing and cloud formation. However, accurate knowledge of the amount of H$_2$O in this atmospheric region is still insufficient due to the difficulty and lack of precise in-situ and space-borne...
A new global UTH dataset, produced within the framework of the EUMETSAT Satellite Application Facility for Climate Monitoring (CM SAF), is presented. The dataset is based on data from 12 polar-orbiting MW sounders operating at 183 GHz that are combined into a single time series covering the period 06/07/94 to 31/12/18. The data are provided on hourly and daily time steps at 1°x1° lat-long....
Water vapor in the Upper Troposphere and Lower Stratosphere (UTLS) is critical to climate feedback mechanisms through its influence on radiation, chemistry, and atmospheric dynamics. The amount of water vapor entering the stratosphere is sensitive to the cold point temperature (CPT), which makes the Northern Hemisphere summer monsoons more favorable for transporting high-water vapor mixing...
Upper tropospheric humidity (UTH) is a crucial diagnostic of the atmospheric water cycle and a significant contributor to climate sensitivity, this highlights the importance of understanding its variability and how it is represented in global climate models.
Initially, using a radiative transfer code, the sensitivity of satellite observations of UTH to temperature and specific humidity is...
