Conveners
Tropospheric Water Vapour
- Michaela Hegglin (U. Reading / FZ Jülich)
Tropospheric Water Vapour
- Helene Brogniez (LSCE/UVSQ)
Tropospheric Water Vapour
- Marc Schröder (DWD)
Tropospheric Water Vapour
- Marc Schröder (DWD)
Over land we find the signal of increasing near-surface water vapour while saturation levels have decreased reasonably robust. Drivers of this, at large scales at least, are reasonably well understood. Over oceans however, uncertainty remains very large with very little agreement between in situ, reanalyses and modelled estimates, very limited spatial coverage of in situ observations, and...
Water vapour is the single most important natural greenhouse gas in the atmosphere, thereby constraining the Earth’s energy balance, directly and indirectly through the water vapour feedback mechanism. In addition, water vapour is a key component of the water cycle. There is consequently the need to consolidate our knowledge of natural variability and past changes in water vapour and to...
Water vapor and clouds are among the fundamental atmospheric components, and as such, are part of the Essential Climate Variable (ECV) monitored by the Global Climate Observing System (GCOS). In this work, the global water vapor Climate Data Record (CDR) generated within the ESA Water Vapor climate change initiative project (WV_cci) is used as reference (daily, 0.1°, 2003-2014) to evaluate a...
The hydrological cycle is a key component of the Earth system, constituting the largest movement of any substance on Earth. Water vapour, while only accounting for 0.001% of all water mass, is an important natural greenhouse gas influencing the radiative balance of the Earth as well as surface and soil moisture fluxes. The time moisture spends in the atmosphere (i.e. the time between...
Water vapor is an essential component in the water and energy cycles of the Arctic. Especially in the light of Arctic amplification, changes in water vapor are of high interest but are difficult to observe due to the sparsity of data in that region. This makes the long-term observations of water vapor at the Arctic research station AWIPEV at Ny-Ålesund, Svalbard, even more valuable: in...
Water vapour is a critical component of the surface radiation budget in the Arctic Ocean due to the strong direct and indirect (clouds) greenhouse effect. The amplified warming of the Arctic and changes in the atmospheric circulation led to positive trends in water vapour. However, due to the sparsity of ground stations and challenges in satellite remote sensing, water vapour estimates and...
The importance of water vapor in arid and hyperarid regions motivates a comparative study in the Atacama and Namib deserts, a natural laboratory to test the role of topography and circulation in present-day climate. Based on ERA5 reanalysis evaluated by satellite and ground-based instruments, we analyzed the total column water vapor (TCWV) from seasonal to interannual scales offshore from...
Tropospheric water vapour isotopologue ratios (expressed as δD) give unique insight into moisture sources and cloud processes, in particular if analysed together with the water vapour concentration.
In this presentation we briefly introduce the theoretical framework of generating {H2O,δD}-pair distributions and we present the MUSICA IASI {H2O,δD}-pair data set (1.5 billion individual data...
Convective mass flux is crucial for understanding convective clouds and their impacts on the ambient environment. A large number of GCM cumulus parameterization schemes rely on this concept, but measuring convective mass flux remains challenging due to the difficulty of capturing vertical air motion within intense convective clouds. No current satellite can measure these motions directly (with...
Water vapor is a key driver of the Earth’s hydrological cycle and plays a critical role in both weather patterns and long-term climate processes. Ground-based GNSS TCWV observations have consistently proven to be accurate and reliable over extended periods. Their consistency with the most precise radiosonde and microwave products is currently within 0.5 – 0.7 kg m-2 in absolute value, with an...
Since 2006, the Metop satellites have orbited the Earth equipped with different instruments to collect atmospheric data. Among them, the GRAS receiver providing GNSS Radio Occultation (GNSS-RO) data, the Infrared Atmospheric Sounding Interferometer (IASI), the Advanced Microwave Sounding Unit (AMSU) and the Microwave Humidity Sounder (MHS).
These sensors operate in different frequency bands...
Atmospheric water vapor is vital in regulating the global energy balance and the hydrological cycle. Accurate estimates of atmospheric water vapor profiles in the troposphere are essential for understanding the mechanisms that control Earth's climate. The temperature and water vapor retrieved from global GNSS radio occultation (RO) data are invaluable for climate studies due to their...
The Microwave Radiometer (MWR) flown on Envisat, ERS-1 and ERS-2, and Sentinel-3 provides a nearly uninterrupted time series of microwave observations between 1991 and 2024. This dataset complements other microwave datasets, e.g. the SSM/I. Despite its nadir-only coverage it provides an opportunity to independently provide estimates on total column water vapor (TCWV) and cloud liquid water...
The launch of the C³IEL (Cluster for Cloud evolution, ClImatE and Lightning) mission, dedicated to convective clouds, is scheduled for 2027 (Rosenfeld et al., 2022). This mission consists in a train of two nano-satellites, which will acquire, at a high spatial and temporal resolution, 4 sequences per day orbit of 11 observations every 20s of 2 simultaneous images. Among the various imagers,...
In this contribution, an algorithm is presented that derives water vapor content in the atmosphere from TROPOMI (on Sentinel-5P) measurements in the near-ultraviolet spectral band. The algorithm, based on a classical differential optical absorption spectroscopy (DOAS) approach, contains some specificities. They concern the use of surface reflectance co-fitted, at pixel level, with the water...
In a warming climate, the expectation is that most regions will experience an increase in extreme precipitation (10 and 50 years) events. The latest IPCC (AR6) report finds that the frequency and intensity of heavy rainfall events “have likely increased at the global scale over a majority of land regions with good observational coverage”. In regions with sparse or no in situ measurements, this...
Our team at the Cooperative Institute for Research in the Atmosphere (CIRA) has begun a multiyear effort to reprocess and extend the NVAP-M global water vapour dataset to span the 40 years from 1988-2027. Satellite microwave observations provide the core data for NVAP. Hypersectral infrared instruments such as AIRS, IASI and CrIS provide a foundation for the 21st century portion of the time...
The ROM SAF second reprocessing (RE2) specific humidity data set is based on radio occultation (RO) refractivity, retrieved by the Metop, COSMIC-1, GRACE, and CHAMP missions. The estimated uncertainties and error correlations of both RO observations and background temperature and specific humidity are determining for the quality of the specific humidity product derived through a...
This paper aimed to validate CMIP6 climate models for climate forecasting in Ethiopia, where station and meteorological observation data were limited. Historical model output data with different spatial and temporal resolutions from 1980 to 2014 was collected from coupled models for inter-comparison phase 6 (CMIP6).
