Validating and Enhancing Extreme Precipitation Projections by Downscaled Global Climate Model Results and Copula Methods

AbstractRealistic reproduction of historical extreme precipitation has been challenging for both reanalysis and global climate model (GCM) simulations. This work assessed the fidelities of the combined gridded observational datasets, reanalysis datasets, and GCMs [CMIP5 and the Chinese Academy of Sciences Flexible Global Ocean–Atmospheric Land System Model–Finite-Volume Atmospheric Model, version 2 (FGOALS-f2)] in representing extreme precipitation over East China. The assessment used 552 stations’ rain gauge data as ground truth and focused on the probability distribution function of daily precipitation and spatial structure of extreme precipitation days. The TRMM observation displays similar rainfall intensity–frequency distributions as the stations. However, three combined gridded observational datasets, four reanalysis datasets, and most of the CMIP5 models cannot capture extreme precipitation exceeding 150 mm day−1, and all underestimate extreme precipitation frequency. The observed spatial distribution of extreme precipitation exhibits two maximum centers, located over the lower-middle reach of Yangtze River basin and the deep South China region, respectively. Combined gridded observations and JRA-55 capture these two centers, but ERA-Interim, MERRA, and CFSR and almost all CMIP5 models fail to capture them. The percentage of extreme rainfall in the total rainfall amount is generally underestimated by 25%–75% in all CMIP5 models. Higher-resolution models tend to have better performance, and physical parameterization may be crucial for simulating correct extreme precipitation. The performances are significantly improved in the newly released FGOALS-f2 as a result of increased resolution and a more realistic simulation of moisture and heating profiles. This work pinpoints the common biases in the combined gridded observational datasets and reanalysis datasets and helps to improve models’ simulation of extreme precipitation, which is critically important for reliable projection of future changes in extreme precipitation.

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Evaluation of extreme sub-daily precipitation in high-resolution global climate model simulations

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2019.0545 ◽

2021 ◽

Vol 379 (2195) ◽

pp. 20190545 ◽

Cited By ~ 1

Author(s):

Michael Wehner ◽

Jiwoo Lee ◽

Mark Risser ◽

Paul Ullrich ◽

Peter Gleckler ◽

...

Keyword(s):

High Resolution ◽

Extreme Precipitation ◽

Climate Models ◽

Climate Model ◽

Daily Precipitation ◽

Flash Flood ◽

Global Climate ◽

Global Climate Model ◽

Model Performance ◽

Horizontal Resolution

We examine the resolution dependence of errors in extreme sub-daily precipitation in available high-resolution climate models. We find that simulated extreme precipitation increases as horizontal resolution increases but that appropriately constructed model skill metrics do not significantly change. We find little evidence that simulated extreme winter or summer storm processes significantly improve with the resolution because the model performance changes identified are consistent with expectations from scale dependence arguments alone. We also discuss the implications of these scale-dependent limitations on the interpretation of simulated extreme precipitation. This article is part of a discussion meeting issue ‘Intensification of short-duration rainfall extremes and implications for flash flood risks’.

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Will Extratropical Storms Intensify in a Warmer Climate?

Journal of Climate ◽

10.1175/2008jcli2678.1 ◽

2009 ◽

Vol 22 (9) ◽

pp. 2276-2301 ◽

Cited By ~ 233

Author(s):

Lennart Bengtsson ◽

Kevin I. Hodges ◽

Noel Keenlyside

Keyword(s):

Extreme Precipitation ◽

Climate Model ◽

Global Climate ◽

Global Climate Model ◽

Extratropical Cyclones ◽

Intergovernmental Panel ◽

Wind Speeds ◽

Central Surface ◽

Extreme Wind Speeds ◽

Global Precipitation

Abstract Extratropical cyclones and how they may change in a warmer climate have been investigated in detail with a high-resolution version of the ECHAM5 global climate model. A spectral resolution of T213 (63 km) is used for two 32-yr periods at the end of the twentieth and twenty-first centuries and integrated for the Intergovernmental Panel on Climate Change (IPCC) A1B scenario. Extremes of pressure, vorticity, wind, and precipitation associated with the cyclones are investigated and compared with a lower-resolution simulation. Comparison with observations of extreme wind speeds indicates that the model reproduces realistic values. This study also investigates the ability of the model to simulate extratropical cyclones by computing composites of intense storms and contrasting them with the same composites from the 40-yr ECMWF Re-Analysis (ERA-40). Composites of the time evolution of intense cyclones are reproduced with great fidelity; in particular the evolution of central surface pressure is almost exactly replicated, but vorticity, maximum wind speed, and precipitation are higher in the model. Spatial composites also show that the distributions of pressure, winds, and precipitation at different stages of the cyclone life cycle compare well with those from ERA-40, as does the vertical structure. For the twenty-first century, changes in the distribution of storms are very similar to those of previous study. There is a small reduction in the number of cyclones but no significant changes in the extremes of wind and vorticity in both hemispheres. There are larger regional changes in agreement with previous studies. The largest changes are in the total precipitation, where a significant increase is seen. Cumulative precipitation along the tracks of the cyclones increases by some 11% per track, or about twice the increase in global precipitation, while the extreme precipitation is close to the globally averaged increase in column water vapor (some 27%). Regionally, changes in extreme precipitation are even higher because of changes in the storm tracks.

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A study of AR, TS, and MCS associated precipitation and extreme precipitation in present and warmer climates

Journal of Climate ◽

10.1175/jcli-d-21-0145.1 ◽

2021 ◽

pp. 1-49

Author(s):

Ming Zhao

Keyword(s):

Extreme Precipitation ◽

Climate Model ◽

Global Climate ◽

Global Climate Model ◽

Regional Distribution ◽

Heavy Precipitation ◽

Global Scale ◽

Central Pacific ◽

South Indian ◽

Global Mean

AbstractAtmospheric rivers (AR), tropical storms (TS) and mesoscale convective systems (MCS) are important weather phenomena which often threaten society through heavy precipitation and strong winds. Despite their potentially vital role in global and regional hydrological cycles, their contributions to long-term mean and extreme precipitation have not been systematically explored at the global scale. Using observational and reanalysis data, and NOAA’s Geophysical Fluid Dynamics Laboratory’s new high-resolution global climate model, we quantify that despite their occasional (13%) occurrence globally, AR, TS, and MCS days together account for ~55% of global mean precipitation and ~75% of extreme precipitation with daily rates exceeding its local 99th percentile. The model reproduces well the observed percentage of mean and extreme precipitation associated with AR, TS and MCS days. In an idealized global warming simulation with a homogeneous 4K SST increase, the modeled changes in global mean and regional distribution of precipitation correspond well with changes in AR/TS/MCS precipitation. Globally, the frequency of AR days increases and migrates towards higher latitudes while the frequency of TS days increases over the central Pacific and part of the South Indian Ocean with a decrease elsewhere. The frequency of MCS days tends to increase over parts of the equatorial western and eastern Pacific warm pools and high latitudes and decreases over most part of the tropics and subtropics. The AR/TS/MCS mean precipitation intensity increases by ~5%/K due primarily to precipitation increases in the top 25% of AR/TS/MCS days with the heaviest precipitation, which are dominated by the thermodynamic component with the dynamic and microphysical components playing a secondary role.

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High bit rate ACTS experiments for performing global science - Keck Telescope and global climate model

10.2514/6.1996-1100 ◽

1996 ◽

Cited By ~ 1

Author(s):

Larry Bergman ◽

J. Gary ◽

Burt Edelson ◽

Neil Helm ◽

Judith Cohen ◽

...

Keyword(s):

Climate Model ◽

Global Climate ◽

Global Climate Model ◽

Bit Rate ◽

Global Science ◽

High Bit Rate

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DEVELOPMENT OF BIAS CORRECTION METHOD FOR TROPICAL CYCLONES IN GLOBAL CLIMATE MODEL AND FUTURE CHANGE PROJECTION OF STORM SURGE USING AMR MODEL

Journal of Japan Society of Civil Engineers Ser B2 (Coastal Engineering) ◽

10.2208/kaigan.74.i_607 ◽

2018 ◽

Vol 74 (2) ◽

pp. I_607-I_612 ◽

Cited By ~ 1

Author(s):

Yosuke YAMAMOTO ◽

Nobuthito MORI ◽

Marc KJERLAND

Keyword(s):

Tropical Cyclones ◽

Storm Surge ◽

Bias Correction ◽

Climate Model ◽

Global Climate ◽

Global Climate Model ◽

Correction Method ◽

Future Change ◽

Bias Correction Method

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A comparison of ship and satellite measurements of cloud properties with global climate model simulations in the southeast Pacific stratus deck

Atmospheric Chemistry and Physics ◽

10.5194/acp-10-6527-2010 ◽

2010 ◽

Vol 10 (14) ◽

pp. 6527-6536 ◽

Cited By ~ 16

Author(s):

M. A. Brunke ◽

S. P. de Szoeke ◽

P. Zuidema ◽

X. Zeng

Keyword(s):

Diurnal Cycle ◽

Climate Model ◽

Global Climate ◽

Global Climate Model ◽

Cloud Fraction ◽

Cloud Base ◽

Liquid Water Path ◽

Cloud Properties ◽

Southeast Pacific ◽

Cloud Thickness

Abstract. Here, liquid water path (LWP), cloud fraction, cloud top height, and cloud base height retrieved by a suite of A-train satellite instruments (the CPR aboard CloudSat, CALIOP aboard CALIPSO, and MODIS aboard Aqua) are compared to ship observations from research cruises made in 2001 and 2003–2007 into the stratus/stratocumulus deck over the southeast Pacific Ocean. It is found that CloudSat radar-only LWP is generally too high over this region and the CloudSat/CALIPSO cloud bases are too low. This results in a relationship (LWP~h9) between CloudSat LWP and CALIPSO cloud thickness (h) that is very different from the adiabatic relationship (LWP~h2) from in situ observations. Such biases can be reduced if LWPs suspected to be contaminated by precipitation are eliminated, as determined by the maximum radar reflectivity Zmax>−15 dBZ in the apparent lower half of the cloud, and if cloud bases are determined based upon the adiabatically-determined cloud thickness (h~LWP1/2). Furthermore, comparing results from a global model (CAM3.1) to ship observations reveals that, while the simulated LWP is quite reasonable, the model cloud is too thick and too low, allowing the model to have LWPs that are almost independent of h. This model can also obtain a reasonable diurnal cycle in LWP and cloud fraction at a location roughly in the centre of this region (20° S, 85° W) but has an opposite diurnal cycle to those observed aboard ship at a location closer to the coast (20° S, 75° W). The diurnal cycle at the latter location is slightly improved in the newest version of the model (CAM4). However, the simulated clouds remain too thick and too low, as cloud bases are usually at or near the surface.

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