The Relative Contribution of Large-Scale Circulation and Land Surface to Summer Precipitation Over Asian Mid-Low Latitudes

Abstract Understanding the contributions of large-scale atmospheric circulation and local land surface processes to precipitation is essentially important for the climate prediction. This study adopts a dynamic adjustment (DA) approach based on constructed circulation analogs to quantitatively isolate the contribution of atmospheric circulation to summer land precipitation (Pr) over Asian mid-low latitudes during 1980-2019. The atmospheric circulation factor is represented by the 500 hPa geopotential height (Z500) from the fifth generation ECMWF reanalysis (ERA5), and the land surface factors, including soil moisture (SM) and net radiation and heat fluxes are from the products of the Global Land Data Assimilation System (GLDAS). The residual component after DA is regarded as the contribution from land surface processes via evaporation mainly resulting from SM. The results indicate that the key SM-Pr feedback areas are mainly located in northeast China and the northern Indian Peninsula. The key influencing area of Z500 on the land Pr anomaly shows a “-+-” tripole pattern in the mid-latitude region. Atmospheric circulation determines the magnitude of summer land Pr, while the residual components reflect the land-atmosphere coupling effect and dominate Pr trend. This conclusion is helpful for better understanding the evolution mechanism of summer climate over Asia mid-low latitudes and may also have application value for climate prediction.

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Land-surface processes and summer-cloud-precipitation characteristics in the Tibetan Plateau and their effects on downstream weather: a review and perspective

National Science Review ◽

10.1093/nsr/nwz226 ◽

2020 ◽

Vol 7 (3) ◽

pp. 500-515 ◽

Cited By ~ 8

Author(s):

Yunfei Fu ◽

Yaoming Ma ◽

Lei Zhong ◽

Yuanjian Yang ◽

Xueliang Guo ◽

...

Keyword(s):

Boundary Layer ◽

Tibetan Plateau ◽

Land Surface ◽

Sensible Heat Flux ◽

Vertical Direction ◽

Heat Fluxes ◽

Surface Processes ◽

Convective Precipitation ◽

The Tibetan Plateau ◽

Land Surface Processes

Abstract Correct understanding of the land-surface processes and cloud-precipitation processes in the Tibetan Plateau (TP) is an important prerequisite for the study and forecast of the downstream activities of weather systems and one of the key points for understanding the global atmospheric movement. In order to show the achievements that have been made, this paper reviews the progress on the observations for the atmospheric boundary layer, land-surface heat fluxes, cloud-precipitation distributions and vertical structures by using ground- and space-based multiplatform, multisensor instruments and the effect of the cloud system in the TP on the downstream weather. The results show that the form drag related to the topography, land–atmosphere momentum and scalar fluxes is an important part of the parameterization process. The sensible heat flux decreased especially in the central and northern TP caused by the decrease in wind speeds and the differences in the ground-air temperatures. Observations show that the cloud and precipitation over the TP have a strong diurnal variation. Studies also show the compressed-air column in the troposphere by the higher-altitude terrain of the TP makes particles inside clouds vary at a shorter distance in the vertical direction than those in the non-plateau area so that precipitation intensity over the TP is usually small with short duration, and the vertical structure of the convective precipitation over the TP is obviously different from that in other regions. In addition, the influence of the TP on severe weather downstream is preliminarily understood from the mechanism. It is necessary to use model simulations and observation techniques to reveal the difference between cloud precipitation in the TP and non-plateau areas in order to understand the cloud microphysical parameters over the TP and the processes of the land boundary layer affecting cloud, precipitation and weather in the downstream regions.

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Quantification of the relative role of land-surface processes and large-scale forcing in dynamic downscaling over the Tibetan Plateau

Climate Dynamics ◽

10.1007/s00382-016-3168-6 ◽

2016 ◽

Vol 48 (5-6) ◽

pp. 1705-1721 ◽

Cited By ~ 31

Author(s):

Yanhong Gao ◽

Linhong Xiao ◽

Deliang Chen ◽

Fei Chen ◽

Jianwei Xu ◽

...

Keyword(s):

Tibetan Plateau ◽

Land Surface ◽

Large Scale ◽

Surface Processes ◽

The Tibetan Plateau ◽

Relative Role ◽

Dynamic Downscaling ◽

Land Surface Processes

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Review of Recent Developments and the Future Prospective in West African Atmosphere/Land Interaction Studies

International Journal of Geophysics ◽

10.1155/2012/748921 ◽

2012 ◽

Vol 2012 ◽

pp. 1-12 ◽

Cited By ~ 13

Author(s):

Yongkang Xue ◽

Aaron Boone ◽

Christopher M. Taylor

Keyword(s):

Land Surface ◽

Large Scale ◽

West African ◽

Surface Processes ◽

Surface Model ◽

African Region ◽

Land Surface Processes ◽

Interaction Studies ◽

African Climate ◽

The Future

This paper reviews West African land/atmosphere interaction studies during the past decade. Four issues are addressed in this paper: land data development, land/atmosphere interactions at seasonal-interannual scales, mesoscale studies, and the future prospective. The development of the AMMA Land Surface Model Intercomparison Project has produced a valuable analysis of the land surface state and fluxes which have been applied in a number of large-scale African regional studies. In seasonal-interannual West African climate studies, the latest evidence from satellite data analyses and modeling studies confirm that the West African region has a climate which is particularly sensitive to land surface processes and there is a strong coupling between land surface processes and regional climate at intraseasonal/seasonal scales. These studies indicate that proper land surface process representations and land status initialization would substantially improve predictions and enhance the predictability of West African climate. Mesoscale studies have revealed new understanding of how soil moisture heterogeneity influences the development of convective storms over the course of the diurnal cycle. Finally, several important issues regarding the future prospective are briefly addressed.

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Response of the surface climate to different land surface models: WRF sensitivity to surface model options

10.5194/egusphere-egu21-15663 ◽

2021 ◽

Author(s):

Daniela C.A. Lima ◽

Rita M. Cardoso ◽

Pedro M.M. Soares

Keyword(s):

Soil Moisture ◽

Land Surface ◽

Wrf Model ◽

Land Surface Model ◽

Heat Fluxes ◽

Surface Processes ◽

Surface Model ◽

Land Surface Models ◽

Land Surface Processes ◽

Surface Models

The Weather Research and Forecasting (WRF) model version 4.2 includes different land surface schemes, allowing a better representation of the land surface processes. Four simulations with the WRF model differing in land surface models and options were investigated as a sensitivity study over the European domain. These experiments span from 2004-2006 with a one-month spin-up and were performed at 0.11o horizontal resolution with 50 vertical levels, following the CORDEX guidelines. The lateral boundary conditions were driven by ERA5 reanalysis from European Centre for Medium-Range Weather Forecasts. For the first experiment, the Noah land surface model was used. For the remaining simulations, the Noah-MP (multi-physics) land surface model was used with different runoff and groundwater options: (1) original surface and subsurface runoff (free drainage), (2) TOPMODEL with groundwater and (3) Miguez-Macho & Fan groundwater scheme. The physical parameterizations options are the same for all simulations. These experiments allow the analysis of the sensitivity of different land surface options and to understand how the representation of land surface processes impacts on the atmosphere properties. This study focusses on the investigation of land-atmosphere feedbacks trough the analysis of the soil moisture &#8211; temperature and soil moisture &#8211; precipitation interactions, latent and sensible heat fluxes, and moisture fluxes. The influence of different surface model options on atmospheric boundary layer is also explored.Acknowledgements. The authors wish to acknowledge the LEADING (PTDC/CTA-MET/28914/2017) project funded by FCT. The authors would like to acknowledge the financial support FCT through project UIDB/50019/2020 &#8211; Instituto Dom Luiz.

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Aggregation effects of surface heterogeneity in land surface processes

Hydrology and Earth System Sciences ◽

10.5194/hess-3-549-1999 ◽

1999 ◽

Vol 3 (4) ◽

pp. 549-563 ◽

Cited By ~ 63

Author(s):

Z. Su ◽

H. Pelgrum ◽

M. Menenti

Keyword(s):

Land Surface ◽

Surface Heterogeneity ◽

Heat Fluxes ◽

Surface Processes ◽

Land Surface Processes ◽

Radiative Fluxes ◽

Heterogeneous Landscapes ◽

Observation Scale ◽

Remote Sensor ◽

Original Observation

Abstract. In order to investigate the aggregation effects of surface heterogeneity in land surface processes we have adapted a theory of aggregation. Two strategies have been adopted: 1) Aggregation of radiative fluxes. The aggregated radiative fluxes are used to derive input parameters that are then used to calculate the aerodynamic fluxes at different aggregation levels. This is equivalent to observing the same area at different resolutions using a certain remote sensor, and then calculating the aerodynamic fluxes correspondingly. 2) Aggregation of aerodynamic fluxes calculated at the original observation scale to different aggregation levels. A case study has been conducted to identify the effects of aggregation on areal estimates of sensible and latent heat fluxes. The length scales of surface variables in heterogeneous landscapes are estimated by means of wavelet analysis.

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An improved representation of the land surface temperature including the effects of vegetation in the COSMO model

10.5194/egusphere-egu2020-22029 ◽

2020 ◽

Author(s):

Jan-Peter Schulz ◽

Gerd Vogel

Keyword(s):

Energy Balance ◽

Surface Energy ◽

Surface Temperature ◽

Land Surface ◽

Surface Energy Balance ◽

Heat Fluxes ◽

Surface Processes ◽

Atmospheric Models ◽

Land Surface Processes ◽

Near Surface

Land surface processes have a significant impact on near-surface atmospheric phenomena. They determine, among others, near-surface sensible and latent heat fluxes and the radiation budget, and thus influence atmosphere and land characteristics, such as temperature and humidity, the structure of the planetary boundary layer, and even cloud formation processes. It is therefore important to simulate the land surface processes in atmospheric models as realistically as possible.Verifications have shown that the amplitude of the diurnal cycle of the surface temperature simulated by the land surface scheme TERRA of the COSMO atmospheric model is systematically underestimated. In contrast, the diurnal cycles of the temperatures in the soil are overestimated, instead. This means that the other components of the surface energy balance are biased as well, for instance, the surface turbulent heat fluxes or the ground heat flux.Data from the Meteorological Observatory Lindenberg of the German Meteorological Service (DWD) were used to analyse this model behaviour. In the standard model configuration of TERRA, there is no representation of the vegetation in the surface energy balance. This means, there is no energy budget including a temperature for the vegetation layer. Furthermore, the insulating effects by the vegetation at the sub-canopy level are missing as well. In this work, a scheme providing both of these missing model characteristics was implemented in TERRA. As a result, the simulated diurnal amplitude of the surface temperature is increased and the one of the soil temperature is reduced, both leading to better agreements with the measurements. These improvements are found in TERRA in offline mode, using Lindenberg observations, as well as in coupled mode in the atmospheric models of DWD, i.e. the limited-area COSMO model and the global ICON model.

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Evolving Paradigms of Climatic Processes and Atmospheric Circulation Affecting Africa

Oxford Research Encyclopedia of Climate Science ◽

10.1093/acrefore/9780190228620.013.515 ◽

2017 ◽

Author(s):

Sharon E. Nicholson

Keyword(s):

Atmospheric Circulation ◽

Land Surface ◽

Field Experiments ◽

Human Impacts ◽

Numerical Models ◽

Climatic Variability ◽

Environmental Variable ◽

Surface Processes ◽

Land Surface Processes ◽

Tropical Rainfall

Classic paradigms describing meteorological phenomena and climate have changed dramatically over the last half-century. This is particularly true for the continent of Africa. Our understanding of its climate is today very different from that which prevailed as recently as the 1960s or 1970s. This article traces the development of relevant paradigms in five broad areas: climate and climate classification, tropical atmospheric circulation, tropical rain-bearing systems, climatic variability and change, and land surface processes and climate. One example is the definition of climate. Originally viewed as simple statistical averages, it is now recognized as an environmental variable with global linkages, multiple timescales of variability, and strong controls via earth surface processes. As a result of numerous field experiments, our understanding of tropical rainfall has morphed from the belief in the domination by local thunderstorms to recognition of vast systems on regional to global scales. Our understanding of the interrelationships with land surface processes has also changed markedly. The simple Charney hypothesis concerning albedo change and the related concept of desertification have given way to a broader view of land–atmosphere interaction. In summary, there has been a major evolution in the way we understand climate, climatic variability, tropical rainfall regimes and rain-bearing systems, and potential human impacts on African climate. Each of these areas has evolved in complexity and understanding, a result of an explosive growth in research and the availability of such investigative tools as satellites, computers, and numerical models.

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