High-resolution simulation of Asian monsoon response to regional uplift of the Tibetan Plateau with regional climate model nested with global climate model

The Tibetan Plateau (TP) and surrounding high mountains constitute an important forcing of the atmospheric circulation due to their height and extent, and thereby impact weather and climate in downstream regions of East Asia. Mesoscale Tibetan Plateau vortices (TPVs) are one of the major precipitation-producing systems on the TP. A fraction of TPVs move off the TP to the east and can trigger extreme precipitation in parts of China, such as the Sichuan province and the Yangtze River valley, which can result in severe flooding. In this study, the climatology of TPV occurrence is examined in two reanalyses and, for the first time, in a high-resolution global climate model using an objective feature tracking algorithm. Most TPVs are generated in the northwestern part of the TP; the center of this main genesis region is small and stable throughout the year. The strength and position of the subtropical westerly jet is correlated to the distance TPVs can travel eastward and therefore could have an effect on whether or not a TPV is moving off the TP. TPV-associated precipitation can account for up to 40% of the total precipitation in parts of China in selected months, often due to individual TPVs. The results show that the global climate model is able to simulate TPVs at N512 (~25 km) horizontal resolution and in general agrees with the reanalyses. The fact that the global climate model can represent the TPV climatology opens a wide range of options for future model-based research on TPVs.

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Effects of coastal topography on climate: high-resolution simulation with a regional climate model

Climate Research ◽

10.3354/cr01077 ◽

2012 ◽

Vol 52 ◽

pp. 159-174 ◽

Cited By ~ 26

Author(s):

B Önol

Keyword(s):

High Resolution ◽

Regional Climate Model ◽

Climate Model ◽

Regional Climate ◽

Resolution Simulation ◽

Coastal Topography

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Direct radiative effects of dust aerosols emitted from the Tibetan Plateau on the East Asian summer monsoon – a regional climate model simulation

10.5194/acp-2017-55 ◽

2017 ◽

Author(s):

Hui Sun ◽

Xiaodong Liu ◽

Zaitao Pan

Keyword(s):

Tibetan Plateau ◽

Regional Climate Model ◽

East Asian Summer Monsoon ◽

Asian Monsoon ◽

Climate Model ◽

Asian Summer Monsoon ◽

Regional Climate ◽

East Asian ◽

Dust Aerosols ◽

Asian Summer

Abstract. While dust aerosols emitted from major Asian sources such as Taklimakan and Gobi Deserts have been shown to have strong effect on Asian monsoon and climate, the role of dust emitted from Tibetan Plateau (TP) itself, where aerosols can directly interact with the TP heat pump because of their physical proximity both in location and elevation, has not been examined. This study uses the dust coupled RegCM4.1 regional climate model to simulate the spatiotemporal distribution of dust aerosols originating in the TP and their radiative effects on the East Asian summer monsoon (EASM) during both heavy and light dust years. Two 20-year simulations with and without the dust emission from TP showed that direct radiative cooling in the mid-troposphere induced by the TP locally produced dust aerosols resulted in an overall anticyclonic circulation anomaly in the low-troposphere centered over the TP region. The northeasterly anomaly in the EASM region reduces its strength considerably. The simulations found a significant negative correlation between the TP column dust load produced by local emissions and the corresponding anomaly in the EASM index (R=−0.41). The locally generated TP dust can cause surface cooling far downstream in eastern Mongolia and northeastern China through stationery Rossby wave propagation. Although contribution to the total Asian dust source from within TP (mainly Qaidam Basin) is relatively small, its impacts on Asian monsoon and climate seems disproportionately large, likely owning to its higher elevation within TP itself.

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Regional climate model experiments to investigate the Asian monsoon in the Late Miocene

Climate of the Past ◽

10.5194/cp-7-847-2011 ◽

2011 ◽

Vol 7 (3) ◽

pp. 847-868 ◽

Cited By ~ 26

Author(s):

H. Tang ◽

A. Micheels ◽

J. Eronen ◽

M. Fortelius

Keyword(s):

Tibetan Plateau ◽

Regional Climate Model ◽

Late Miocene ◽

Asian Monsoon ◽

Climate Model ◽

Regional Climate ◽

Northern China ◽

Regional Model ◽

Monsoon Climate ◽

Northern Tibetan Plateau

Abstract. The Late Miocene (11.6–5.3 Ma) is a crucial period in the history of the Asian monsoon. Significant changes in the Asian climate regime have been documented for this period, which saw the formation of the modern Asian monsoon system. However, the spatiotemporal structure of these changes is still ambiguous, and the associated mechanisms are debated. Here, we present a simulation of the average state of the Asian monsoon climate for the Tortonian (11–7 Ma) using the regional climate model CCLM3.2. We employ relatively high spatial resolution (1° × 1°) and adapt the physical boundary conditions such as topography, land-sea distribution and vegetation in the regional model to represent the Late Miocene. As climatological forcing, the output of a Tortonian run with a fully-coupled atmosphere-ocean general circulation model is used. Our regional Tortonian run shows a stronger-than-present East Asian winter monsoon wind as a result of the enhanced mid-latitude westerly wind of our global forcing and the lowered present-day northern Tibetan Plateau in the regional model. The summer monsoon circulation is generally weakened in our regional Tortonian run compared to today. However, the changes of summer monsoon precipitation exhibit major regional differences. Precipitation decreases in northern China and northern India, but increases in southern China, the western coast and the southern tip of India. This can be attributed to the changes in both the regional topography (e.g. the lower northern Tibetan Plateau) and the global climate conditions (e.g. the higher sea surface temperature). The spread of dry summer conditions over northern China and northern Pakistan in our Tortonian run further implies that the monsoonal climate may not have been fully established in these regions in the Tortonian. Compared with the global model, the high resolution regional model highlights the spatial differences of the Asian monsoon climate in the Tortonian, and better characterizes the convective activity and its response to regional topographical changes. It therefore provides a useful and compared to global models, a complementary tool to improve our understanding of the Asian monsoon evolution in the Late Miocene.

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Coordinated Global and Regional Climate Modeling*

Journal of Climate ◽

10.1175/jcli-d-15-0161.1 ◽

2015 ◽

Vol 29 (1) ◽

pp. 17-35 ◽

Cited By ~ 102

Author(s):

J. F. Scinocca ◽

V. V. Kharin ◽

Y. Jiao ◽

M. W. Qian ◽

M. Lazare ◽

...

Keyword(s):

Regional Climate Model ◽

Climate Model ◽

Climate Modeling ◽

Global Climate ◽

Global Climate Model ◽

Regional Climate ◽

Value Added ◽

Regional Climate Modeling ◽

Climate Projections ◽

Climate Modelling

Abstract A new approach of coordinated global and regional climate modeling is presented. It is applied to the Canadian Centre for Climate Modelling and Analysis Regional Climate Model (CanRCM4) and its parent global climate model CanESM2. CanRCM4 was developed specifically to downscale climate predictions and climate projections made by its parent global model. The close association of a regional climate model (RCM) with a parent global climate model (GCM) offers novel avenues of model development and application that are not typically available to independent regional climate modeling centers. For example, when CanRCM4 is driven by its parent model, driving information for all of its prognostic variables is available (including aerosols and chemical species), significantly improving the quality of their simulation. Additionally, CanRCM4 can be driven by its parent model for all downscaling applications by employing a spectral nudging procedure in CanESM2 designed to constrain its evolution to follow any large-scale driving data. Coordination offers benefit to the development of physical parameterizations and provides an objective means to evaluate the scalability of such parameterizations across a range of spatial resolutions. Finally, coordinating regional and global modeling efforts helps to highlight the importance of assessing RCMs’ value added relative to their driving global models. As a first step in this direction, a framework for identifying appreciable differences in RCM versus GCM climate change results is proposed and applied to CanRCM4 and CanESM2.

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Brief Communication: An update of the article "Modeling flood damages under climate change conditions – a case study for Germany"

Natural Hazards and Earth System Sciences Discussions ◽

10.5194/nhessd-3-7231-2015 ◽

2015 ◽

Vol 3 (12) ◽

pp. 7231-7245

Author(s):

F. F. Hattermann ◽

S. Huang ◽

O. Burghoff ◽

P. Hoffmann ◽

Z. W. Kundzewicz

Keyword(s):

Climate Change ◽

Regional Climate Model ◽

Large Scale ◽

Considerable Increase ◽

Climate Model ◽

Global Climate ◽

Global Climate Model ◽

Regional Climate ◽

Flood Damages

Abstract. In our first study on possible flood damages under climate change in Germany, we reported that a considerable increase in flood related losses can be expected in future, warmer, climate. However, the general significance of the study was limited by the fact that outcome of only one Global Climate Model (GCM) was used as large scale climate driver, while many studies report that GCM models are often the largest source of uncertainty in impact modeling. Here we show that a much broader set of global and regional climate model combinations as climate driver shows trends which are in line with the original results and even give a stronger increase of damages.

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On the Seasonal Forecasting of Regional Tropical Cyclone Activity

Journal of Climate ◽

10.1175/jcli-d-14-00158.1 ◽

2014 ◽

Vol 27 (21) ◽

pp. 7994-8016 ◽

Cited By ~ 231

Author(s):

G. A. Vecchi ◽

T. Delworth ◽

R. Gudgel ◽

S. Kapnick ◽

A. Rosati ◽

...

Keyword(s):

High Resolution ◽

Climate Model ◽

Global Climate ◽

Spatial Scales ◽

Global Climate Model ◽

Regional Climate ◽

Weather Extremes ◽

Moderate Resolution ◽

Systematic Biases ◽

Constrained Conditions

Abstract Tropical cyclones (TCs) are a hazard to life and property and a prominent element of the global climate system; therefore, understanding and predicting TC location, intensity, and frequency is of both societal and scientific significance. Methodologies exist to predict basinwide, seasonally aggregated TC activity months, seasons, and even years in advance. It is shown that a newly developed high-resolution global climate model can produce skillful forecasts of seasonal TC activity on spatial scales finer than basinwide, from months and seasons in advance of the TC season. The climate model used here is targeted at predicting regional climate and the statistics of weather extremes on seasonal to decadal time scales, and comprises high-resolution (50 km × 50 km) atmosphere and land components as well as more moderate-resolution (~100 km) sea ice and ocean components. The simulation of TC climatology and interannual variations in this climate model is substantially improved by correcting systematic ocean biases through “flux adjustment.” A suite of 12-month duration retrospective forecasts is performed over the 1981–2012 period, after initializing the climate model to observationally constrained conditions at the start of each forecast period, using both the standard and flux-adjusted versions of the model. The standard and flux-adjusted forecasts exhibit equivalent skill at predicting Northern Hemisphere TC season sea surface temperature, but the flux-adjusted model exhibits substantially improved basinwide and regional TC activity forecasts, highlighting the role of systematic biases in limiting the quality of TC forecasts. These results suggest that dynamical forecasts of seasonally aggregated regional TC activity months in advance are feasible.

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Global climate model and coupled regional climate model simulations over the eastern United States: GENESIS and RegCM2 simulations

Global and Planetary Change ◽

10.1016/s0921-8181(96)00011-2 ◽

1997 ◽

Vol 15 (1-2) ◽

pp. 3-32 ◽

Cited By ~ 18

Author(s):

G.S. Jenkins ◽

E.J. Barron

Keyword(s):

United States ◽

Regional Climate Model ◽

Climate Model ◽

Global Climate ◽

Global Climate Model ◽

Regional Climate ◽

Eastern United States ◽

Model Simulations ◽

Climate Model Simulations

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Future Climate in the Tibetan Plateau from a Statistical Regional Climate Model

Journal of Climate ◽

10.1175/jcli-d-13-00187.1 ◽

2013 ◽

Vol 26 (24) ◽

pp. 10125-10138 ◽

Cited By ~ 29

Author(s):

Xiuhua Zhu ◽

Weiqiang Wang ◽

Klaus Fraedrich

Keyword(s):

Tibetan Plateau ◽

Regional Climate Model ◽

Climate Model ◽

Regional Climate ◽

Early Summer ◽

Maximum Temperature ◽

Boreal Summer ◽

The Tibetan Plateau ◽

Temperature Trends ◽

Precipitation Increase

Abstract The authors use a statistical regional climate model [Statistical Regional Model (STAR)] to project the Tibetan Plateau (TP) climate for the period 2015–50. Reanalysis datasets covering 1958–2001 are used as a substitute of observations and resampled by STAR to optimally fit prescribed linear temperature trends derived from the Max Planck Institute Earth System Model (MPI-ESM) simulations for phase 5 of the Coupled Model Intercomparison Project (CMIP5) under the representative concentration pathway 2.6 (RCP2.6) and RCP4.5 scenarios. To assess the related uncertainty, temperature trends from carefully selected best/worst ensemble members are considered. In addition, an extra projection is forced by observed temperature trends in 1958–2001. The following results are obtained: (i) Spatial average temperature will increase by 0.6°–0.9°C; the increase exceeds 1°C in all months except in boreal summer, thus indicating a reduced annual cycle; and daily minimum temperature rises faster than daily maximum temperature, resulting in a narrowing of the diurnal range of near-surface temperature. (ii) Precipitation increase mainly occurs in early summer and autumn possibly because of an earlier onset and later withdrawal of the Asian summer monsoon. (iii) Both frost and ice days decrease by 1–2 days in spring, early summer, and autumn, and the decrease of frost days on the annual course is inversely related to the precipitation increase. (iv) Degree-days increase all over the TP with peak amplitude in the Qaidam Basin and the southern TP periphery, which will result in distinct melting of the local seasonal frozen ground, and the annual temperature range will decrease with stronger amplitude in south TP.

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