Sensitivity to horizontal resolution of regional climate model in simulated precipitation over Kyushu in Baiu season

Abstract The hydrostatic regional climate model RCA, version 3 (RCA3), of the Swedish Meteorological and Hydrological Institute was used to dynamically downscale ERA-40 and the ECMWF operational analysis over a 22-yr period. Downscaling was performed at four horizontal resolutions—50, 25, 12.5, and 6.25 km—over an identical European domain. The model-simulated precipitation is evaluated against high-resolution gridded observational precipitation datasets over Switzerland and southern Norway, regions that are characterized by complex orography and distinct climate regimes. RCA3 generally overestimates precipitation over high mountains: during winter and summer over Switzerland and during summer over central-southern Norway. In the summer, this is linked with a substantial contribution of convective precipitation to the total precipitation errors, especially at the coarser resolutions (50 and 25 km). A general improvement in spatial correlation coefficients between simulated and observed precipitation is observed when the horizontal resolution is increased from 50 to 6 km. The 95th percentile spatial correlation coefficients during winter are much higher for southern Norway than for Switzerland, indicating that RCA3 is more successful at reproducing a relatively simple west-to-east precipitation gradient over southern Norway than a much more complex and variable precipitation distribution over Switzerland. The 6-km simulation is not always superior to the other simulations, possibly indicating that the model dynamical and physical configuration at this resolution may not have been optimal. However, a general improvement in simulated precipitation with increasing resolution supports further use and application of high spatial resolutions in RCA3.

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Validation of the HIRHAM-Simulated Indian Summer Monsoon Circulation

Advances in Meteorology ◽

10.1155/2010/415632 ◽

2010 ◽

Vol 2010 ◽

pp. 1-14 ◽

Cited By ~ 15

Author(s):

Stefan Polanski ◽

Annette Rinke ◽

Klaus Dethloff

Keyword(s):

Summer Monsoon ◽

Climate Model ◽

Regional Climate ◽

Horizontal Resolution ◽

Monsoon Circulation ◽

Data Sets ◽

Data Set ◽

Topographic Features ◽

Temperature And Precipitation ◽

Simulated Precipitation

The regional climate model HIRHAM has been applied over the Asian continent to simulate the Indian monsoon circulation under present-day conditions. The model is driven at the lateral and lower boundaries by European reanalysis (ERA40) data for the period from 1958 to 2001. Simulations with a horizontal resolution of 50 km are carried out to analyze the regional monsoon patterns. The focus in this paper is on the validation of the long-term summer monsoon climatology and its variability concerning circulation, temperature, and precipitation. Additionally, the monsoonal behavior in simulations for wet and dry years has been investigated and compared against several observational data sets. The results successfully reproduce the observations due to a realistic reproduction of topographic features. The simulated precipitation shows a better agreement with a high-resolution gridded precipitation data set over the central land areas of India and in the higher elevated Tibetan and Himalayan regions than ERA40.

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Panama’s Current Climate Replicability in a Non-Hydrostatic Regional Climate Model Nested in an Atmospheric General Circulation Model

Atmosphere ◽

10.3390/atmos12121543 ◽

2021 ◽

Vol 12 (12) ◽

pp. 1543

Author(s):

Reinhardt Pinzón ◽

Noriko N. Ishizaki ◽

Hidetaka Sasaki ◽

Tosiyuki Nakaegawa

Keyword(s):

Regional Climate Model ◽

Air Temperature ◽

General Circulation ◽

Climate Model ◽

Regional Climate ◽

Surface Air Temperature ◽

Circulation Model ◽

Horizontal Resolution ◽

Temperature And Precipitation ◽

Current Climate

To simulate the current climate, a 20-year integration of a non-hydrostatic regional climate model (NHRCM) with grid spacing of 5 and 2 km (NHRCM05 and NHRCM02, respectively) was nested within the AGCM. The three models did a similarly good job of simulating surface air temperature, and the spatial horizontal resolution did not affect these statistics. NHRCM02 did a good job of reproducing seasonal variations in surface air temperature. NHRCM05 overestimated annual mean precipitation in the western part of Panama and eastern part of the Pacific Ocean. NHRCM05 is responsible for this overestimation because it is not seen in MRI-AGCM. NHRCM02 simulated annual mean precipitation better than NHRCM05, probably due to a convection-permitting model without a convection scheme, such as the Kain and Fritsch scheme. Therefore, the finer horizontal resolution of NHRCM02 did a better job of replicating the current climatological mean geographical distributions and seasonal changes of surface air temperature and precipitation.

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Assessing the Effects of Spatial Resolution on Regional Climate Model Simulated Summer Temperature and Precipitation in China: A Case Study

Advances in Meteorology ◽

10.1155/2016/7639567 ◽

2016 ◽

Vol 2016 ◽

pp. 1-12 ◽

Cited By ~ 4

Author(s):

Xin-Min Zeng ◽

Ming Wang ◽

Yujian Zhang ◽

Yang Wang ◽

Yiqun Zheng

Keyword(s):

Regional Climate Model ◽

South China ◽

Climate Model ◽

Regional Climate ◽

Surface Air Temperature ◽

Northern China ◽

Horizontal Resolution ◽

Vertical Resolution ◽

Humid Climate ◽

Entire Area

The regional climate model, RegCM3, is used to simulate the 2004 summer surface air temperature (SAT) and precipitation at different horizontal (i.e., 30, 60, and 90 km) and vertical resolutions (i.e., 14, 18, and 23 layers). Results showed that increasing resolution evidently changes simulated SATs with regional characteristics. For example, simulated SATs are apparently better produced when horizontal resolution increases from 60 to 30 km under the 23 layers. Meanwhile, the SATs over the entire area are more sensitive to vertical resolution than horizontal resolution. The subareas present higher sensitivities than the total area, with larger horizontal resolution effects than those of vertical resolution. For precipitation, increasing resolution shows higher impact compared to SAT, with higher sensitivity induced by vertical resolution than by horizontal resolution, especially in rainy South China. The best SAT/precipitation can be produced only when the horizontal and vertical resolutions are reasonably configured. This indicates that different resolutions lead to different atmospheric thermodynamic states. Because of the dry climate and low soil heat capacity in Northern China, resolution changes easily modify surface energy fluxes, hence the SAT; due to the rainy and humid climate in South China, resolution changes likely strongly influence grid-scale structure of clouds and therefore precipitation.

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Sensitivity of an Arctic regional climate model to the horizontal resolution during winter: implications for aerosol simulation

International Journal of Climatology ◽

10.1002/joc.1205 ◽

2005 ◽

Vol 25 (11) ◽

pp. 1455-1471 ◽

Cited By ~ 6

Author(s):

Eric Girard ◽

Biljana Bekcic

Keyword(s):

Regional Climate Model ◽

Climate Model ◽

Regional Climate ◽

Horizontal Resolution

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Antarctic 20th Century Accumulation Changes Based on Regional Climate Model Simulations

Advances in Meteorology ◽

10.1155/2010/327172 ◽

2010 ◽

Vol 2010 ◽

pp. 1-14 ◽

Cited By ~ 8

Author(s):

Klaus Dethloff ◽

Ksenia Glushak ◽

Annette Rinke ◽

Dörthe Handorf

Keyword(s):

Regional Climate Model ◽

Climate Model ◽

Regional Climate ◽

Reanalysis Data ◽

Horizontal Resolution ◽

East Antarctica ◽

Transient Pressure ◽

Near Surface ◽

Surface Mass ◽

The Antarctic

The regional climate model HIRHAM has been applied to Antarctica driven at the lateral and lower boundaries by European Reanalysis data ERA-40 for the period 1958–1998. Simulations over 4 decades, carried out with a horizontal resolution of 50 km, deliver a realistic simulation of the Antarctic atmospheric circulation, synoptic-scale pressure systems, and the spatial distribution of precipitation minus sublimation (P-E) structures. The simulated P-E pattern is in qualitative agreement with glaciological estimates. The estimated (P-E) trends demonstrate surfacemass accumulation increase at the West Antarctic coasts and reductions in parts of East Antarctica. The influence of the Antarctic Oscillation (AAO) on the near-surface climate and the surface mass accumulation over Antarctica have been investigated on the basis of ERA-40 data and HIRHAM simulations. It is shown that the regional accumulation changes are largely driven by changes in the transient activity around the Antarctic coasts due to the varying AAO phases. During positive AAO, more transient pressure systems travelling towards the continent, and Western Antarctica and parts of South-Eastern Antarctica gain more precipitation and mass. Over central Antarctica the prevailing anticyclone causes a strengthening of polar desertification connected with a reduced surface mass balance in the northern part of East Antarctica.

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Impacts of different RCP scenarios on ALADIN-Climate regional climate model projections over Hungary

10.5194/egusphere-egu2020-15871 ◽

2020 ◽

Author(s):

Beatrix Bán ◽

Gabriella Zsebeházi

Keyword(s):

Regional Climate Model ◽

Climate Model ◽

Regional Climate ◽

Horizontal Resolution ◽

Observation Data ◽

Rcp Scenarios ◽

Local Climate ◽

Temperature And Precipitation ◽

Local Climate Change ◽

Primary Basis

The KlimAdat national project was started in 2016 to create a complex database of detailed meteorological information aiming to support local climate change impact studies in different sectors, adaptation strategies and related decision making. Besides observation data its primary basis will be ALADIN-Climate and REMO regional climate model simulations achieved by the Hungarian Meteorological Service and this set of projections will be extended by members of the Euro-CORDEX ensemble in order to quantify the projection uncertainties.&#160; This study is focusing on analysis of the ALADIN-Climate model projections driven with RCP4.5 and RCP8.5 scenarios. Firstly, the CNRM-CM5 global model outputs were downscaled to 50 km horizontal resolution over the EURO-CORDEX domain with ALADIN-Climate Version 5.2. Then using these &#160;results as lateral boundary conditions, 10 km experiments were prepared on a domain covering Central and South-Eastern Europe. The presentation aims to introduce the behaviour of these simulations achieved by different scenarios and at different spatial resolution from the aspect of temperature and precipitation change over Hungary. Special attention will be put on the differences in extreme indices. Finally, our 10 km resolution simulations are compared with EURO-CORDEX results to specify their place in a larger ensemble.

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Evaluation of Agriculture-Related Climate Indices in Hindcast COSMO-CLM Simulations over Central Europe

Environmental Sciences Proceedings ◽

10.3390/ecas2020-08464 ◽

2020 ◽

Vol 4 (1) ◽

pp. 27

Author(s):

Huan Zhang ◽

Merja H. Tölle

Keyword(s):

Regional Climate Model ◽

Central Europe ◽

Climate Model ◽

Crop Yields ◽

Regional Climate ◽

Growing Season ◽

Horizontal Resolution ◽

Climate Indices ◽

Climate Projections ◽

Growing Season Length

High horizontal resolution regional climate model simulations serve as forcing data for crop and dynamic vegetation models, for generating possible scenarios of the future effects of climate change on crop yields and pollinators. Here, we performed convection-permitting hindcast simulations with the regional climate model COSMO5.0-CLM15 (CCLM) from 1979 to 2015, and the first year was considered as a spin-up period. The model was driven with hourly ERA5 data, which were the latest climate reanalysis product by ECMWF, and directly downscaled to a 3 km horizontal resolution over Central Europe. The land-use classes were described by ECOCLIMAP, and the soil type and depth were described by HWSD. The evaluation was carried out in terms of temperature, precipitation, and climate indices, comparing CCLM output with the gridded observational dataset HYRAS from the German Weather Service. While CCLM inherits a warm and dry summer bias found in its parent model, it reproduces the main features of the recent past climate of Central Europe, including the seasonal mean climate patterns and probability density distributions. Furthermore, the model reproduced climate indices for temperature like growing season length, growing season start date, number of summer days. The results highlighted the possibility of directly downscaling ERA5 data with regional climate models, avoiding the multiple nesting approach and high computational costs. This study adds confidence to convection-permitting climate projections of future changes in agricultural climate indices.

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Assessment of Various Bias Correction Methods on Precipitation of Regional Climate Model and Future Projection

10.21203/rs.3.rs-339080/v1 ◽

2021 ◽

Author(s):

Gunavathi S ◽

Selvasidhu R

Keyword(s):

Regional Climate Model ◽

Bias Correction ◽

Climate Model ◽

Rainwater Harvesting ◽

Regional Climate ◽

Power Transformation ◽

Northeast Monsoon ◽

Correction Technique ◽

Simulated Precipitation ◽

The Future

Abstract The application of regional climate model simulations (RCMs) in climate change impact studies is challengeable due to the risk of possible biases. Some sort of correction needs to be done prior to the application of RCM simulations. This study attempts to assess the performance of a simple (linear scaling and Delta Change method) and complex correction technique (Local intensity scaling, Power transformation and Distribution mapping) on CORDEX(Coordinated Regional Climate Downscaling Experiment)simulated precipitation series for the Thanjavur district. The performance at annual resolution is evaluated using various statistical parameters such as Correlation, Root Mean Square Error and Bias against the observed precipitation data. The raw RCM estimates were improved significantly after the bias correction with all methods. However, Power transformation exhibits good agreement with the observed data at the district level than other methods because it corrects both the mean and variance. The future climate was projected from 2021 to 2100 for RCP 4.5 and RCP 8.5 scenarios. The temporal distribution of future precipitation clearly shows that most of the years will receive heavy precipitation; rather, some years will receive low and average precipitation. The spatial distribution pattern indicates that the northeast monsoon will dominate over all the ranges and places. This study has provided clear information on future precipitation to the environmentalist, urban planners, and policymakers to take appropriate mitigation measures towards agriculture and disaster management. Rainwater harvesting, recharging the aquifers, afforestation, and redirecting the excess amount of water to the river through proper channels is the plausible actions suggested overcoming excessive precipitation in the future.

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Analysing the bandwidths of hydrological change in small river catchments using an ensemble of high-resolution regional climate model projections

10.5194/egusphere-egu21-8611 ◽

2021 ◽

Author(s):

Christoph Sauer ◽

Peter Fröhle ◽

Edgar Nehlsen ◽

Diana Rechid ◽

Laurens Bouwer ◽

...

Keyword(s):

Regional Climate Model ◽

Temporal Resolution ◽

21St Century ◽

Climate Model ◽

Regional Climate ◽

Small River ◽

Precipitation Extremes ◽

Climate Modelling ◽

Simulated Precipitation ◽

River Catchments

Projections of the 21st century potential future climate evolution, especially for precipitation, are associated with high uncertainty and variability. Knowledge of the variability of the projected precipitation and resulting run-offs and the sources of uncertainties form the basis for analysis and assessment of future water-management options as well as potential risks related to droughts and flood events. The variabilities related to climate modelling can only be assessed by using a comparatively large number of climate projections.In our research, we apply a large ensemble of regional climate model projections from the regional climate model REMO, driven by different global climate model simulations, at high temporal (hourly timestep) and high spatial (0.11 degree, or about 12.5 km) resolutions. Although the analysis of such big datasets involves considerable computational and storage capacities, this potentially helps to improve the simulation of future hydrological quantities in river catchments. For the analysis of the behaviour of small river catchments, we apply a semi-distributive hydrological model. Annual and winter average precipitation conditions show a robust and statistically significant increase especially for the RCP8.5 scenario. Precipitation ranges are compared with the ranges of runoff based on hydrological impact model runs driven by a set of simulated parameters from the regional climate model ensemble. The analyses are performed for a sub-catchment of the Lower Elbe system (Kr&#252;ckau catchment), which is a typical small basin (area < 200km2) close to the city of Hamburg in northern Germany. The model runs cover a long simulation period of 150 years (1950-2100) with a temporal resolution of 1 day. Short term model runs with a temporal resolution of 1 hour were carried out for annual and seasonal (summer/winter) maximum runoff derived from the long-term simulations.Average annual runoff shows an increase of 0 to 10 % for the RCP2.6 ensemble and an increase of 0 to 20 % for the RCP8.5 ensemble at the end of the 21st century. Annual and winter average conditions (precipitation sums and average runoff) of the RCP8.5 ensemble show a robust increase across different ensemble simulations. Extreme events however show high variability and no conclusive and robust trend. Analysis shows a good relation between average values of precipitation and average runoff (MQ). Future development of simulated annual maximum runoffs shows only a weak relation with future simulated precipitation extremes. However, summer maximum runoffs tend to show a relation with summer precipitation extremes. The behaviour of winter runoffs might be explained by altered future conditions of snow aggregation and melt in combination with high soil moisture. With increasing average and extreme temperatures, snow fall, snow accumulation and concentrated runoff caused by snow melt in spring are less likely to occur.One of the conclusions drawn is that especially for assessing extreme precipitation and its impacts on small hydrological catchments it is necessary to apply regional climate model projections with high spatial and temporal resolution where further improvement is expected by making use of the upcoming generation of climate simulations on convection permitting scale.

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