Investigating the mechanisms of diurnal rainfall variability over Peninsular Malaysia using the non-hydrostatic regional climate model

Abstract Climate change is one of the challenging global issues that our world is facing and it is intensely debated on the international agenda. It is a fact that climate change has brought about many disastrous events on a global scale which affect our livelihoods. Climate models are commonly used by researchers to study the magnitude of the changing climate and to simulate future climate projections. Most climate models are developed based on various interactions among the Earth’s climate components such as the land surface, oceans, atmosphere and sea-ice. In this study, the second-generation Canadian Earth System Model (CanESM2) was statistically downscaled to develop a regional climate model (RCM) based on three representative concentration pathways (RCPs): RCP2.6, RCP4.5 and RCP8.5. The RCM will be used to simulate the average minimum and maximum temperatures and average precipitation for Ipoh, Subang and KLIA Sepang in Peninsular Malaysia for the years 2006 to 2100. The simulated data were bias corrected using the historical observation data of monthly average minimum and maximum temperatures and monthly average rainfall retrieved from the Malaysian Meteorological Department (MMD). The different trends of the simulated data for all the three locations based on the RCP2.6, RCP4.5 and RCP8.5 were evaluated for future climate projection.

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Idealized SST anomaly regional climate model experiments: A note of caution

Progress in Physical Geography Earth and Environment ◽

10.1177/0309133309356738 ◽

2010 ◽

Vol 34 (1) ◽

pp. 59-74 ◽

Cited By ~ 2

Author(s):

C.J.R. Williams ◽

D.R. Kniveton ◽

R. Layberry

Keyword(s):

Atlantic Ocean ◽

Regional Climate Model ◽

Southern Africa ◽

General Circulation ◽

Climate Model ◽

Rainfall Variability ◽

Regional Climate ◽

Model Experiments ◽

Southern Atlantic Ocean ◽

Sst Anomalies

To date, a number of studies have focused on the influence of sea surface temperature (SST) on global and regional rainfall variability, with the majority of these focusing on certain ocean basins — eg, the Pacific, North Atlantic and Indian Ocean. In contrast, relatively less work has been done on the influence of the central South Atlantic, particularly in relation to rainfall over southern Africa. Previous work by the authors, using reanalysis data and general circulation model (GCM) experiments, has suggested that cold SST anomalies in the central southern Atlantic Ocean are linked to an increase in rainfall extremes across southern Africa. In this paper we present results from idealized regional climate model (RCM) experiments forced with both positive and negative SST anomalies in the southern Atlantic Ocean. These experiments reveal an unexpected response of rainfall over southern Africa. In particular, it was found that SST anomalies of opposite sign can cause similar rainfall responses in the model experiments, with isolated increases in rainfall over central southern Africa as well as a large region of drying over the Mozambique Channel. The purpose of this paper is to highlight this finding and explore explanations for the behaviour of the climate model. It is suggested that the observed changes in rainfall might result from the redistribution of energy (associated with upper-level changes to Rossby waves) or, of more concern, model error, and therefore the paper concludes that the results of idealized regional climate models forced with SST anomalies should be viewed cautiously.

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An original way to evaluate daily rainfall variability simulated by a regional climate model: the case of South African austral summer rainfall

International Journal of Climatology ◽

10.1002/joc.4155 ◽

2014 ◽

Vol 35 (9) ◽

pp. 2485-2502 ◽

Cited By ~ 3

Author(s):

Julien Crétat ◽

Benjamin Pohl ◽

Carmela Chateau Smith ◽

Nicolas Vigaud ◽

Yves Richard

Keyword(s):

Regional Climate Model ◽

South African ◽

Climate Model ◽

Rainfall Variability ◽

Regional Climate ◽

Austral Summer ◽

Daily Rainfall ◽

Summer Rainfall

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Rainfall Variability under Present and Future Climate Scenarios Using the Rossby Center Bias-Corrected Regional Climate Model

American Journal of Climate Change ◽

10.4236/ajcc.2020.93016 ◽

2020 ◽

Vol 09 (03) ◽

pp. 243-265

Author(s):

Jane Wangui Mugo ◽

Franklin J. Opijah ◽

Joshua Ngaina ◽

Faith Karanja ◽

Mary Mburu

Keyword(s):

Regional Climate Model ◽

Climate Model ◽

Rainfall Variability ◽

Regional Climate ◽

Future Climate ◽

Climate Scenarios ◽

Center Bias

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Urbanization and Rainfall Variability in the Beijing Metropolitan Region

Journal of Hydrometeorology ◽

10.1175/jhm-d-13-0180.1 ◽

2014 ◽

Vol 15 (6) ◽

pp. 2219-2235 ◽

Cited By ~ 38

Author(s):

Yan Zhang ◽

James A. Smith ◽

Lifeng Luo ◽

Zifa Wang ◽

Mary Lynn Baeck

Keyword(s):

Regional Climate Model ◽

Climate Model ◽

Rainfall Variability ◽

Regional Climate ◽

Wrf Model ◽

Surface Energy Budget ◽

Metropolitan Region ◽

Spatial And Temporal Variability ◽

Model Simulations ◽

Climate Model Simulations

Abstract In this study, rainfall variability in the Beijing metropolitan region and its link to urbanization during the first 10 years of the twenty-first century (2000–09) was examined. Analyses are based on both observations and regional climate model simulations. The study was focused on August, one of the summer months that receive most of the warm season precipitation in Beijing. Observations from surface stations and weather radars in Beijing and its surrounding regions along with satellite observations from the Tropical Rainfall Measuring Mission (TRMM) are used to characterize the spatial and temporal variability of precipitation. It is found that the urban area has fewer rain days and higher rainfall intensity compared to its surrounding region. This suggests a possible impact of urbanization on the spatial variability of rainfall for the region. Regional climate model simulations with the Weather Research and Forecasting (WRF) Model are thus performed with two land use–land cover datasets that represent different stages of urbanization in the Beijing metropolitan region to investigate such an impact. The modeling study demonstrates how urbanization modifies the surface energy budget and the planetary boundary layer, which in turn affects the production of precipitation.

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Investigating the Mechanisms of Diurnal Rainfall Variability Using a Regional Climate Model

Journal of Climate ◽

10.1175/jcli-d-11-00616.1 ◽

2012 ◽

Vol 25 (20) ◽

pp. 7232-7247 ◽

Cited By ~ 52

Author(s):

Jason P. Evans ◽

Seth Westra

Keyword(s):

Regional Climate Model ◽

Diurnal Cycle ◽

Large Scale ◽

Climate Model ◽

Rainfall Variability ◽

Regional Climate ◽

Convective Precipitation ◽

Regional Variability ◽

Diurnal Variability ◽

Diurnal Cycles

Abstract This study investigates the ability of a regional climate model (RCM) to simulate the diurnal cycle of precipitation over southeast Australia, to provide a basis for understanding the mechanisms that drive diurnal variability. When compared with 195 observation gauges, the RCM tends to simulate too many occurrences and too little intensity for precipitation events at the 3-hourly time scale. However, the overall precipitation amounts are well simulated and the diurnal variability in occurrences and intensities are generally well reproduced, particularly in spring and summer. In terms of precipitation amounts, the RCM overestimated the diurnal cycle during the warmer months but was reasonably accurate during winter. The timing of the maxima and minima was found to match the observed timings well. The spatial pattern of diurnal variability in the Weather Research and Forecasting model outputs was remarkably similar to the observed record, capturing many features of regional variability. The RCM diurnal cycle was dominated by the convective (subgrid scale) precipitation. In the RCM the diurnal cycle of convective precipitation over land corresponds well to atmospheric instability and thermally triggered convection over large areas, and also to the large-scale moisture convergence at 700 hPa along the east coast, with the strongest diurnal cycles present where these three mechanisms are in phase.

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Interactions among ENSO, the Monsoon, and Diurnal Cycle in Rainfall Variability over Java, Indonesia

Journal of the Atmospheric Sciences ◽

10.1175/2010jas3348.1 ◽

2010 ◽

Vol 67 (11) ◽

pp. 3509-3524 ◽

Cited By ~ 84

Author(s):

Jian-Hua Qian ◽

Andrew W. Robertson ◽

Vincent Moron

Keyword(s):

Regional Climate Model ◽

Diurnal Cycle ◽

El Niño ◽

Climate Model ◽

El Nino ◽

Rainfall Variability ◽

Regional Climate ◽

Theoretical Physics ◽

Northern Coast ◽

Wet Season

Abstract Using a high-resolution regional climate model—the Abdus Salam International Centre for Theoretical Physics Regional Climate Model version 3 (RegCM3)—and station and satellite observations, the authors have studied the spatial heterogeneity of climate variability over Java Island, Indonesia. Besides the well-known anomalous dry conditions that characterize the dry and transition seasons during an El Niño year, analysis of regional model output reveals a wet mountainous south versus dry northern plains in precipitation anomalies associated with El Niño over Java during the peak rainy season. Modeling experiments indicate that this mountains/plains contrast is caused by the interaction of the El Niño–induced monsoonal wind anomalies and the island/mountain-induced local diurnal cycle of winds and precipitation. During the wet season of El Niño years, anomalous southeasterly winds over the Indonesian region oppose the climatological northwesterly monsoon, thus reducing the strength of the monsoon winds over Java. This weakening is found to amplify the local diurnal cycle of land–sea breezes and mountain–valley winds, producing more rainfall over the mountains, which are located closer to the southern coast than to the northern coast. Therefore, the variability of the diurnal cycle associated with this local spatial asymmetry of topography is the underlying cause for the heterogeneous pattern of wet south/dry north rainfall anomalies during El Niño years. It is further shown that the mean southeasterly wind anomalies during December–February of El Niño years result from more frequent occurrence of a quiescent monsoon weather type, during which the strengthened sea-breeze and valley-breeze convergence leads to above normal rainfall over the mountains.

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