Investigation of the atmospheric water budget of the BALTEX area using NCEP/NCAR reanalysis data

Abstract With the motivation to identify whether a reasonably simulated atmospheric circulation would necessarily lead to a successful reproduction of monsoon precipitation, the performances of five sets of reanalysis data [NCEP–U.S. Department of Energy (DOE) Atmospheric Model Intercomparison Project II (AMIP-II) reanalysis (NCEP-2), 40-yr ECMWF Re-Analysis (ERA-40), Japanese 25-yr Reanalysis Project (JRA-25), Interim ECMWF Re-Analysis (ERA-Interim), and Modern-Era Retrospective Analysis for Research and Applications (MERRA)] in reproducing the climatology, interannual variation, and long-term trend of global monsoon (GM) precipitation are comprehensively evaluated. To better understand the variability and long-term trend of GM precipitation, the authors also examined the major components of water budget, including evaporation, water vapor convergence, and the change in local column water vapor, based on the five reanalysis datasets. Results show that all five reanalysis datasets reasonably reproduce the climatology of GM precipitation. ERA-Interim (NCEP-2) shows the highest (lowest) skill among the five datasets. The observed GM precipitation shows an increasing tendency during 1979–2011 along with a strong interannual variability, which is reasonably reproduced by five reanalysis datasets. The observed increasing trend of GM precipitation is dominated by contributions from the Asian, North American, Southern African, and Australian monsoons. All five datasets fail in reproducing the increasing tendency of the North African monsoon precipitation. The wind convergence term in the water budget equation dominates the GM precipitation variation, indicating a consistency between the GM precipitation and the seasonal change of prevailing wind.

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Water Budget on Various Land Use Areas Using NARR Reanalysis Data in Florida

Advances in Meteorology ◽

10.1155/2011/351350 ◽

2011 ◽

Vol 2011 ◽

pp. 1-13 ◽

Cited By ~ 1

Author(s):

Chi-Han Cheng ◽

Fidelia Nnadi

Keyword(s):

Land Use ◽

Soil Moisture ◽

Water Budget ◽

Urban Forest ◽

Primary Source ◽

Reanalysis Data ◽

Rooting Depth ◽

Drought Event ◽

Rainfall Anomalies ◽

Regional Reanalysis

1992 to 2002 data from North American Regional Reanalysis (NARR) were used to investigate water budget on five land use areas: urban, forest, agriculture, lake, and wetland in the state of Florida, USA. The data were evaluated based on the anomalies of rainfall, evaporation, and soil moisture from the average condition. The anomalies were used to investigate the effect of extreme conditions on water budget parameters for various land uses in both northeast and south of Florida. The results showed that extreme events such as La Niña strongly affected the water budget on land-use areas in both regions as the negative monthly rainfall anomalies were observed during the 1999-2000 event, while EI Niño and thunderstorms in summer caused positive rainfall anomalies with more than 70% in all study areas. Higher rainfall led to higher soil moisture anomalies for the agriculture, forest, and wetland from 1992 to May 1998 in both study regions. However, soil moisture becomes primary source for evaporation in drier conditions, and differences in capacity of plants access water, often dictated by the rooting depth, can result in contrasting evaporative losses across vegetation types. Hence, the forest, which had the deeper roots, had lower soil moisture anomalies, but higher evaporation anomalies than agriculture area during the drought event.

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Implications of Improved Representation of Convection for the East Africa Water Budget Using a Convection-Permitting Model

Journal of Climate ◽

10.1175/jcli-d-18-0387.1 ◽

2019 ◽

Vol 32 (7) ◽

pp. 2109-2129 ◽

Cited By ~ 18

Author(s):

Declan L. Finney ◽

John H. Marsham ◽

Lawrence S. Jackson ◽

Elizabeth J. Kendon ◽

David P. Rowell ◽

...

Keyword(s):

East Africa ◽

Water Budget ◽

Large Scale ◽

Lake Victoria ◽

Regional Climate ◽

Moisture Flux ◽

Land Breeze ◽

Moist Convection ◽

Atmospheric Water ◽

Lake Victoria Basin

Abstract The precipitation and diabatic heating resulting from moist convection make it a key component of the atmospheric water budget in the tropics. With convective parameterization being a known source of uncertainty in global models, convection-permitting (CP) models are increasingly being used to improve understanding of regional climate. Here, a new 10-yr CP simulation is used to study the characteristics of rainfall and atmospheric water budget for East Africa and the Lake Victoria basin. The explicit representation of convection leads to a widespread improvement in the intensities and diurnal cycle of rainfall when compared with a parameterized simulation. Differences in large-scale moisture fluxes lead to a shift in the mean rainfall pattern from the Congo to Lake Victoria basin in the CP simulation—highlighting the important connection between local changes in the representation of convection and larger-scale dynamics and rainfall. Stronger lake–land contrasts in buoyancy in the CP model lead to a stronger nocturnal land breeze over Lake Victoria, increasing evaporation and moisture flux convergence (MFC), and likely unrealistically high rainfall. However, for the mountains east of the lake, the CP model produces a diurnal rainfall cycle much more similar to satellite estimates, which is related to differences in the timing of MFC. Results here demonstrate that, while care is needed regarding lake forcings, a CP approach offers a more realistic representation of several rainfall characteristics through a more physically based realization of the atmospheric dynamics around the complex topography of East Africa.

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How is the atmospheric residence time of evapotranspired water altered with a dried-up lake or a forest restoration scenario and what is the impact on precipiation?

10.5194/egusphere-egu21-7368 ◽

2021 ◽

Author(s):

Jianhui Wei ◽

Joël Arnault ◽

Zhenyu Zhang ◽

Patrick Laux ◽

Benjamin Fersch ◽

...

Keyword(s):

Land Use ◽

Residence Time ◽

Water Budget ◽

Forest Restoration ◽

Water Cycle ◽

Wrf Model ◽

Atmospheric Water ◽

Budget Analysis ◽

Precipitation Recycling ◽

The Impact

Land surface characteristics and processes may have complex interactions with the physical and dynamical processes of the atmosphere. However, adequate methods for systemically understanding individual processes of the nonlinearly coupled land-atmosphere continuum are still rare. Therefore, in this study, the age-weighted evaporation tagging approach of Wei et al. (2016) and the three-dimensional online atmospheric water budget analysis of Arnault et al. (2016) were implemented into the Weather Research and Forecast (WRF) model. In addition to the total and tagged atmospheric water states of matter, the latter approach was further extended for age-weighted tagged atmospheric water states of matter, thereby providing a prognostic equation of the residence time of state variables in the atmospheric water cycle. This extension allows to systematically quantify the fate of evaporated and transpired water in terms of magnitude, location, composition, and residence time. The extended WRF model was tested for a land use and land cover change study for the Poyang Lake basin, the largest freshwater lake in China. Two hypothetical scenarios, i.e., a dried-up lake and a forest restoration scenario, were simulated and then compared to a real-case control simulation using the original land-use data. The results of the basin-scale precipitation recycling in the context of evapotranspiration partitioning and the modified atmospheric water cycle due to both scenarios will be presented and discussed. We conclude that our newly developed modelling framework and the proposed analysis strategy have the potential to be applied for better understanding and quantifying the nonlinearly intertwined processes between the land and the atmosphere.References:Arnault, J., Knoche, R., Wei, J., & Kunstmann, H. (2016). Evaporation tagging and atmospheric water budget analysis with WRF: A regional precipitation recycling study for West Africa. Water Resources Research, 52(3), 1544&#8211;1567. https://doi.org/10.1002/2015WR017704Wei, J., Knoche, R., & Kunstmann, H. (2016). Atmospheric residence times from transpiration and evaporation to precipitation: An age-weighted regional evaporation tagging approach. Journal of Geophysical Research: Atmospheres, 121(12), 6841&#8211;6862. https://doi.org/10.1002/2015JD024650

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