Numerical Simulation of Fluxes Generated by Inhomogeneities of the Underlying Surface over the Jinta Oasisin Northwestern China |
| |
Authors: | LI Wanli LU Shihu FU Shenming MENG Xianhong and H C NNAMCHI |
| |
Institution: | Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions, Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences, Lanzhou 730000, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029,Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions, Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences, Lanzhou 730000,Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029,Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000,Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, Department of Geography, University of Nigeria, Nsukka, Nigeria |
| |
Abstract: | Using land-use types derived from satellite remote sensing data collected by
the EOS Moderate Resolution Imaging Spectroradiometer (EOS/MODIS), the
mesoscale and turbulent fluxes generated by inhomogeneities of the
underlying surface over the Jinta Oasis, northwestern China, were
simulated using the Regional Atmospheric Modeling System (RAMS4.4). The
results indicate that mesoscale circulation generated by land-surface
inhomogeneities over the Jinta Oasis is more important than turbulence.
Vertical heat fluxes and water vapor are transported to higher levels by
mesoscale circulation. Mesoscale circulation also produces mesoscale
synoptic systems and prevents water vapor over the oasis from running off.
Mesoscale circulation transports moisture to higher atmospheric levels as
the land-surface moisture over the oasis increases, favoring the formation
of clouds, which sometimes leads to rainfall. Large-scale wind speed has a
significant impact on mesoscale heat fluxes. During the active phase of
mesoscale circulation, the stronger large-scale winds are associated with
small mesoscale fluxes; however, background wind seems to intensify the
turbulent sensible heat flux and turbulent latent heat flux. If the area of
oasis is enlarged properly, mesoscale circulation will be able to transport
moisture to higher levels, favoring the formation of rainfall in the oasis
and protecting its ``cold island' effect. The impact of irrigation on
rainfall is important, and increasing irrigation across the oasis is
necessary to protect the oasis. |
| |
Keywords: | inhomogeneities RAMS mesoscale circulation turbulence heat flux |
本文献已被 CNKI SpringerLink 等数据库收录! |
| 点击此处可从《大气科学进展》浏览原始摘要信息 |
| 点击此处可从《大气科学进展》下载免费的PDF全文 |
|