A Regional Model Simulation of the 1991 Severe Precipitation Event over the Yangtze–Huai River Valley. Part I: Precipitation and Circulation Statistics

Abstract. The drainage of the Fucino Lake of central Italy was completed in 1873, and this possibly caused significant climatic changes over the Fucino basin. In this paper we discuss a set of short-term triple-nested regional model simulations of the meteorological effects of the Fucino Lake on the surrounding region. We find that the model simulates realistic lake-breeze circulations and their response to background winds. The simulations indicate that the lake affects the temperature of the surrounding basin in all seasons and precipitation in the cold season, when cyclonic perturbations move across the region. Some effects of the lake also extend over areas quite far from the Fucino basin. Our results support the hypothesis that the drainage of the lake might have significantly affected the climate of the lake basin. However, longer simulations and further development in some aspects of the model are needed, in order to provide a more statistically robust evaluation of the simulated lake-effects.Key words. Hydrology (anthropogenic effects) – Meteorology and atmospheric dynamics (climatology; mesoscale meteorology)

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Specification of External Forcing for Regional Model Integrations

Monthly Weather Review ◽

10.1175/2008mwr2654.1 ◽

2009 ◽

Vol 137 (4) ◽

pp. 1409-1421 ◽

Cited By ~ 13

Author(s):

K. Yoshimura ◽

M. Kanamitsu

Keyword(s):

Model Simulation ◽

Interpolation Method ◽

Vertical Direction ◽

Regional Model ◽

Vertical Resolution ◽

Time Frequency ◽

Spectral Nudging ◽

External Forcings ◽

Large Numbers ◽

Regional Simulation

Abstract The effect of vertical and time interpolations of external forcings on the accuracy of regional simulations is examined. Two different treatments of the forcings, one with conventional lateral boundary nudging and the other with spectral nudging, are studied. The main result is that the accuracy of the regional simulation increases very slowly as the number of forcing field levels increase when no spectral nudging is used. Thus, for better simulation, it is desirable to have as many forcing levels as possible. By contrast, spectral nudging improves the regional model simulation when reasonably large numbers of forcing field levels, at least up to nine levels, are given. The accuracy worsens drastically when the number of forcing levels is reduced to less than nine. To improve the simulation, in particular when the forcing field is given at a coarse vertical resolution and at lower time frequency, an incremental interpolation method is introduced. The incremental interpolation in the vertical direction significantly improves the regional simulation at all numbers of forcing field levels. The improvement is largest at very low vertical resolution. Incremental interpolation in time also works excellently, allowing the use of daily output for reasonably accurate downscaling. By using a combination of spectral nudging and incremental interpolation, it is possible to make a reasonably accurate downscaling from the forcing given daily at three–five levels in the vertical direction with low overhead. This considerably reduces the amount of data currently believed to be required to downscale global model integrations.

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Regional model simulation of North Atlantic cyclones: Present climate and idealized response to increased sea surface temperature

Journal of Geophysical Research Atmospheres ◽

10.1029/2006jd008213 ◽

2008 ◽

Vol 113 (D2) ◽

Cited By ~ 11

Author(s):

Tido Semmler ◽

Saji Varghese ◽

Ray McGrath ◽

Paul Nolan ◽

Shiyu Wang ◽

...

Keyword(s):

Surface Temperature ◽

Sea Surface Temperature ◽

North Atlantic ◽

Model Simulation ◽

Regional Model ◽

Sea Surface ◽

Present Climate

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Long Term Environmental Change in the Huai River Valley, 200 B.C.E.-1855

Engineering the State ◽

10.4324/9781315811116-2 ◽

2018 ◽

pp. 3-21

Author(s):

David A. Pietz

Keyword(s):

Environmental Change ◽

River Valley ◽

Huai River

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Regional model simulation of the North Atlantic cyclone "Caroline" and comparisons with satellite data

Annales Geophysicae ◽

10.5194/angeo-21-655-2003 ◽

2003 ◽

Vol 21 (3) ◽

pp. 655-659

Author(s):

E. Keup-Thiel ◽

C.-Ph. Klepp ◽

E. Raschke ◽

B. Rockel

Keyword(s):

Satellite Data ◽

North Atlantic ◽

North Atlantic Ocean ◽

Water Cycle ◽

Model Simulation ◽

Precipitation Amount ◽

Regional Model ◽

Radio Science ◽

The North ◽

The North Atlantic

Abstract. An individual regional model simulation of cyclone "Caroline" has been carried out to study water cycle components over the North Atlantic Ocean. The uncertainties associated with quantitative estimates of the water cycle components are highlighted by a comparison of the model results with SSM/I (Special Sensor Microwave Imager) satellite data. The vertically integrated water vapor of the REgional MOdel REMO is in good agreement with the SSM/I satellite data. The simulation results for other water budget components like the vertically integrated liquid water content and precipitation compare also reasonably well within the frontal system. However, the high precipitation rate in the cold air outbreak on the backside of the cold front derived from SSM/I satellite data is generally underestimated by REMO. This results in a considerable deficit of the total precipitation amount accumulated for the cyclone "Caroline". While REMO simulates 24.3 108 m3 h-1 for 09:00 UTC, the total areal precipitation from SSM/I satellite data amounts to 54.7 08 m3 h-1.Key words. Meteorology and atmospheric dynamics (precipitation; mesoscale meteorology) – Radio science (remote sensing)

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Simulations in the Topography Effects of Tianshan Mountains on an Extreme Precipitation Event in the Ili River Valley, China

Atmosphere ◽

10.3390/atmos12060750 ◽

2021 ◽

Vol 12 (6) ◽

pp. 750

Author(s):

Yufang Min ◽

Wanlong Huang ◽

Minjin Ma ◽

Yaonan Zhang

Keyword(s):

Water Vapor ◽

Extreme Precipitation ◽

Tianshan Mountains ◽

River Valley ◽

Extreme Precipitation Event ◽

Precipitation Event ◽

Upward Movement ◽

Ili River Valley ◽

Wide Range ◽

Windward Slope

Xinjiang is located in an arid and semi-arid climate region in China, but Xinjiang Ili river valley is more humid, with higher precipitation intensity and precipitation, which is closely related to the role of the Tianshan Mountains. In this paper, through the NCRP 1° × 1° reanalysis data and the conventional observation data of the Ili River Valley in Xinjiang, the terrain sensitivity experiment conducted by the WRF model is used to analyze the short-term extreme precipitation event of the Ili River Valley from 18–19 of May 2017, to reveal the influence of Tianshan Mountains on the extreme precipitation event of the Ili River Valley. The results show that: (1) The reduction or removal of the terrain will cause a wide range of wind field changes, weaken the vertical upward movement of the windward slope, and the accumulation of water vapor before the windward slope will also be reduced; a large-scale change of the terrain will also affect the direction of water vapor transportation. These effects together lead to a decrease or increase in regional precipitation. (2) “Fuzzy” (smooth) terrain will affect the precipitation simulated by changing the local vertical movement and water vapor transport, which shows that the WRF model’s accurate description of the terrain structure characteristics of mountainous areas is beneficial to accurately simulate the precipitation process on the windward slope area.

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