Regional temperature and precipitation changes under high-end (≥4
            °
            C) global warming

Climate models vary widely in their projections of both global mean temperature rise and regional climate changes, but are there any systematic differences in regional changes associated with different levels of global climate sensitivity? This paper examines model projections of climate change over the twenty-first century from the Intergovernmental Panel on Climate Change Fourth Assessment Report which used the A2 scenario from the IPCC Special Report on Emissions Scenarios, assessing whether different regional responses can be seen in models categorized as ‘high-end’ (those projecting 4 ° C or more by the end of the twenty-first century relative to the preindustrial). It also identifies regions where the largest climate changes are projected under high-end warming. The mean spatial patterns of change, normalized against the global rate of warming, are generally similar in high-end and ‘non-high-end’ simulations. The exception is the higher latitudes, where land areas warm relatively faster in boreal summer in high-end models, but sea ice areas show varying differences in boreal winter. Many continental interiors warm approximately twice as fast as the global average, with this being particularly accentuated in boreal summer, and the winter-time Arctic Ocean temperatures rise more than three times faster than the global average. Large temperature increases and precipitation decreases are projected in some of the regions that currently experience water resource pressures, including Mediterranean fringe regions, indicating enhanced pressure on water resources in these areas.

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Climate Change Projection in the Twenty-First Century Simulated by NIMS-KMA CMIP6 Model Based on New GHGs Concentration Pathways

Asia-Pacific Journal of Atmospheric Sciences ◽

10.1007/s13143-021-00225-6 ◽

2021 ◽

Author(s):

Hyun Min Sung ◽

Jisun Kim ◽

Sungbo Shim ◽

Jeong-byn Seo ◽

Sang-Hoon Kwon ◽

...

Keyword(s):

Climate Change ◽

Climate Changes ◽

Scientific Information ◽

Earth System Model ◽

First Century ◽

System Model ◽

The Arctic ◽

Earth System ◽

Future Projections ◽

Twenty First Century

AbstractThe National Institute of Meteorological Sciences-Korea Meteorological Administration (NIMS-KMA) has participated in the Coupled Model Inter-comparison Project (CMIP) and provided long-term simulations using the coupled climate model. The NIMS-KMA produces new future projections using the ensemble mean of KMA Advanced Community Earth system model (K-ACE) and UK Earth System Model version1 (UKESM1) simulations to provide scientific information of future climate changes. In this study, we analyze four experiments those conducted following the new shared socioeconomic pathway (SSP) based scenarios to examine projected climate change in the twenty-first century. Present day (PD) simulations show high performance skill in both climate mean and variability, which provide a reliability of the climate models and reduces the uncertainty in response to future forcing. In future projections, global temperature increases from 1.92 °C to 5.20 °C relative to the PD level (1995–2014). Global mean precipitation increases from 5.1% to 10.1% and sea ice extent decreases from 19% to 62% in the Arctic and from 18% to 54% in the Antarctic. In addition, climate changes are accelerating toward the late twenty-first century. Our CMIP6 simulations are released to the public through the Earth System Grid Federation (ESGF) international data sharing portal and are used to support the establishment of the national adaptation plan for climate change in South Korea.

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An Assessment of Recent and Future Temperature Change over the Sichuan Basin, China, Using CMIP5 Climate Models

Journal of Climate ◽

10.1175/jcli-d-16-0536.1 ◽

2017 ◽

Vol 30 (17) ◽

pp. 6701-6722 ◽

Cited By ~ 15

Author(s):

Daniel Bannister ◽

Michael Herzog ◽

Hans-F. Graf ◽

J. Scott Hosking ◽

C. Alan Short

Keyword(s):

Climate Change ◽

Sichuan Basin ◽

Climate Models ◽

Distribution Functions ◽

Future Climate ◽

First Century ◽

Future Climate Change ◽

Change Scenario ◽

The Sichuan Basin ◽

Twenty First Century

The Sichuan basin is one of the most densely populated regions of China, making the area particularly vulnerable to the adverse impacts associated with future climate change. As such, climate models are important for understanding regional and local impacts of climate change and variability, like heat stress and drought. In this study, climate models from phase 5 of the Coupled Model Intercomparison Project (CMIP5) are validated over the Sichuan basin by evaluating how well each model can capture the phase, amplitude, and variability of the regionally observed mean, maximum, and minimum temperature between 1979 and 2005. The results reveal that the majority of the models do not capture the basic spatial pattern and observed means, trends, and probability distribution functions. In particular, mean and minimum temperatures are underestimated, especially during the winter, resulting in biases exceeding −3°C. Models that reasonably represent the complex basin topography are found to generally have lower biases overall. The five most skillful climate models with respect to the regional climate of the Sichuan basin are selected to explore twenty-first-century temperature projections for the region. Under the CMIP5 high-emission future climate change scenario, representative concentration pathway 8.5 (RCP8.5), the temperatures are projected to increase by approximately 4°C (with an average warming rate of +0.72°C decade−1), with the greatest warming located over the central plains of the Sichuan basin, by 2100. Moreover, the frequency of extreme months (where mean temperature exceeds 28°C) is shown to increase in the twenty-first century at a faster rate compared to the twentieth century.

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CLIMATE CHANGE SCENARIOS FOR THE U.S. NATIONAL ASSESSMENT

Bulletin of the American Meteorological Society ◽

10.1175/bams-84-12-1711 ◽

2003 ◽

Vol 84 (12) ◽

pp. 1711-1724 ◽

Cited By ~ 24

Author(s):

Michael C. MacCracken ◽

Eric J. Barron ◽

David R. Easterling ◽

Benjamin S. Felzer ◽

Thomas R. Karl

Keyword(s):

Climate Change ◽

Twentieth Century ◽

Climate Models ◽

Climatic Conditions ◽

First Century ◽

Climate Change Scenarios ◽

Climate Scenarios ◽

National Assessment ◽

Twenty First Century ◽

The U.S

In support of the U.S. National Assessment of the Potential Consequences of Climate Variability and Change, climate scenarios were prepared to serve as the basis for evaluating the vulnerability of environmental and societal systems to changes projected for the twenty-first century. Since publication of the results of the assessment at the end of 2000, the National Research Council's report Climate Change Science: An Analysis of Some Key Questions, and the U.S. government's U.S. Climate Action Report—2002 have both relied on the assessment's findings. Because of the importance of these findings, it is important to directly address questions regarding the representativeness and usefulness of the model-based projections on which the findings were based. In particular, criticisms have focused on whether the climate models that were relied upon adequately represented twentieth-century conditions and whether their projections of conditions for the twenty-first century were outliers. Reexamination of the approach used in developing and evaluating the climate scenarios indicates that the results from the two primary climate modeling groups that were relied upon allowed the generation of climate scenarios that span much of the range of possible future climatic conditions projected by the larger set of model simulations, which was compiled for the IPCCs Third Assessment Report. With the set of models showing increasing agreement in their simulations of twentieth-century trends in climate and of projected changes in climate on subcontinental to continental scales, the climate scenarios that were generated seem likely to provide a plausible representation of the types of climatic conditions that could be experienced during the twenty-first century. Warming, reduced snow cover, and more intense heavy precipitation events were projected by all models, suggesting such changes are quite likely. However, significant differences remain in the projection of changes in precipitation and of the regional departures in climate from the larger-scale patterns. For this reason, evaluating potential impacts using climate scenarios based on models exhibiting different regional responses is a necessary step to ensuring a representative analysis. Utilizing an even more encompassing set of scenarios in the future could help move from mainly qualitative toward more certain and quantitative conclusions.

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Projected Response of Tropical Cyclone Intensity and Intensification in a Global Climate Model

Journal of Climate ◽

10.1175/jcli-d-17-0898.1 ◽

2018 ◽

Vol 31 (20) ◽

pp. 8281-8303 ◽

Cited By ~ 48

Author(s):

Kieran Bhatia ◽

Gabriel Vecchi ◽

Hiroyuki Murakami ◽

Seth Underwood ◽

James Kossin

Keyword(s):

Climate Change ◽

Radiative Forcing ◽

Climate Models ◽

Control Experiment ◽

Climate Model ◽

Global Climate ◽

Global Climate Model ◽

First Century ◽

Geophysical Fluid Dynamics Laboratory ◽

Twenty First Century

As one of the first global coupled climate models to simulate and predict category 4 and 5 (Saffir–Simpson scale) tropical cyclones (TCs) and their interannual variations, the High-Resolution Forecast-Oriented Low Ocean Resolution (HiFLOR) model at the Geophysical Fluid Dynamics Laboratory (GFDL) represents a novel source of insight on how the entire TC intensification distribution could be transformed because of climate change. In this study, three 70-yr HiFLOR experiments are performed to identify the effects of climate change on TC intensity and intensification. For each of the experiments, sea surface temperature (SST) is nudged to different climatological targets and atmospheric radiative forcing is specified, allowing us to explore the sensitivity of TCs to these conditions. First, a control experiment, which uses prescribed climatological ocean and radiative forcing based on observations during the years 1986–2005, is compared to two observational records and evaluated for its ability to capture the mean TC behavior during these years. The simulated intensification distributions as well as the percentage of TCs that become major hurricanes show similarities with observations. The control experiment is then compared to two twenty-first-century experiments, in which the climatological SSTs from the control experiment are perturbed by multimodel projected SST anomalies and atmospheric radiative forcing from either 2016–35 or 2081–2100 (RCP4.5 scenario). The frequency, intensity, and intensification distribution of TCs all shift to higher values as the twenty-first century progresses. HiFLOR’s unique response to climate change and fidelity in simulating the present climate lays the groundwork for future studies involving models of this type.

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A Hybrid Dynamical–Statistical Downscaling Technique. Part II: End-of-Century Warming Projections Predict a New Climate State in the Los Angeles Region

Journal of Climate ◽

10.1175/jcli-d-14-00197.1 ◽

2015 ◽

Vol 28 (12) ◽

pp. 4618-4636 ◽

Cited By ~ 24

Author(s):

Fengpeng Sun ◽

Daniel B. Walton ◽

Alex Hall

Keyword(s):

Climate Change ◽

Los Angeles ◽

Climate Models ◽

Greenhouse Gas Emission ◽

Regional Scale ◽

Global Climate Models ◽

First Century ◽

Climate Change Signal ◽

Uncertainty Estimates ◽

Twenty First Century

Abstract Using the hybrid downscaling technique developed in part I of this study, temperature changes relative to a baseline period (1981–2000) in the greater Los Angeles region are downscaled for two future time slices: midcentury (2041–60) and end of century (2081–2100). Two representative concentration pathways (RCPs) are considered, corresponding to greenhouse gas emission reductions over coming decades (RCP2.6) and to continued twenty-first-century emissions increases (RCP8.5). All available global climate models from phase 5 of the Coupled Model Intercomparison Project (CMIP5) are downscaled to provide likelihood and uncertainty estimates. By the end of century under RCP8.5, a distinctly new regional climate state emerges: average temperatures will almost certainly be outside the interannual variability range seen in the baseline. Except for the highest elevations and a narrow swath very near the coast, land locations will likely see 60–90 additional extremely hot days per year, effectively adding a new season of extreme heat. In mountainous areas, a majority of the many baseline days with freezing nighttime temperatures will most likely not occur. According to a similarity metric that measures daily temperature variability and the climate change signal, the RCP8.5 end-of-century climate will most likely be only about 50% similar to the baseline. For midcentury under RCP2.6 and RCP8.5 and end of century under RCP2.6, these same measures also indicate a detectable though less significant climatic shift. Therefore, while measures reducing global emissions would not prevent climate change at this regional scale in the coming decades, their impact would be dramatic by the end of the twenty-first century.

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Heavy Precipitation Events in a Warmer Climate: Results from CMIP5 Models

Journal of Climate ◽

10.1175/jcli-d-12-00850.1 ◽

2013 ◽

Vol 26 (20) ◽

pp. 7902-7911 ◽

Cited By ~ 85

Author(s):

Enrico Scoccimarro ◽

Silvio Gualdi ◽

Alessio Bellucci ◽

Matteo Zampieri ◽

Antonio Navarra

Keyword(s):

Heavy Precipitation ◽

First Century ◽

Cmip5 Models ◽

Boreal Summer ◽

Boreal Winter ◽

Precipitation Distribution ◽

Twenty First Century ◽

The Difference ◽

The Right ◽

Precipitation Events

Abstract In this work, the authors investigate possible changes in the distribution of heavy precipitation events under a warmer climate, using the results of a set of 20 climate models taking part in phase 5 of Coupled Model Intercomparison Project (CMIP5). Future changes are evaluated as the difference between the last four decades of the twenty-first century and the twentieth century, assuming the representative concentration pathway 8.5 (RCP8.5) scenario. As a measure of the width of the right tail of the precipitation distribution, the authors use the difference between the 99th and the 90th percentiles. Despite a slight tendency to underestimate the observed heavy precipitation, the considered CMIP5 models well represent the observed patterns in terms of the ensemble average, during both boreal summer and winter seasons for the 1997–2005 period. Future changes in average precipitation are consistent with previous findings based on models from phase 3 of CMIP (CMIP3). CMIP5 models show a projected increase for the end of the twenty-first century of the width of the right tail of the precipitation distribution, particularly pronounced over India, Southeast Asia, Indonesia, and central Africa during boreal summer, as well as over South America and southern Africa during boreal winter.

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Consensus on Twenty-First-Century Rainfall Projections in Climate Models More Widespread than Previously Thought

Journal of Climate ◽

10.1175/jcli-d-11-00354.1 ◽

2012 ◽

Vol 25 (11) ◽

pp. 3792-3809 ◽

Cited By ~ 74

Author(s):

Scott B. Power ◽

François Delage ◽

Robert Colman ◽

Aurel Moise

Keyword(s):

Climate Change ◽

Climate Models ◽

Statistical Significance ◽

First Century ◽

Intergovernmental Panel ◽

Ipcc Report ◽

Projected Change ◽

Twenty First Century ◽

The Impact ◽

Precipitation Projections

Under global warming, increases in precipitation are expected at high latitudes and near major tropical convergence zones in some seasons, while decreases are expected in many subtropical and midlatitude areas in between. In many other areas there is no consensus among models on the sign of the projected change. This is often assumed to indicate that precipitation projections in these regions are highly uncertain. Here, twenty-first century precipitation projections under the Special Report on Emissions Scenarios (SRES) A1B scenario using 24 World Climate Research Programme (WCRP)/Coupled Model Intercomparison Project phase 3 (CMIP3) climate models are examined. In areas with no consensus on the sign of projected change there are extensive subregions where the projected change is “very likely” (i.e., probability > 0.90) to be small (relative to, e.g., the size of interannual variability during the late twentieth century) or zero. The statistical significance of and interrelationships between methods used to identify model consensus on projected change in the 2007 Intergovernmental Panel on Climate Change (IPCC) report are examined, and the impact of interdependency among model projections on statistical significance is investigated. Interdependency among projections is shown to be much weaker than interdependency among simulations of climatology. The results show that there is more widespread consistency among the model projections than one might infer from the 2007 IPCC Fourth Assessment report. This discovery highlights the broader need to identify regions, variables, and phenomena that are expected to be little affected by anthropogenic climate change and to communicate this information to the wider community. This is especially important for projections of climate for the next 1–3 decades.

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Changes in the Risk of Cool-Season Tornadoes over Southern Australia due to Model Projections of Anthropogenic Warming

Journal of Climate ◽

10.1175/2009jcli3456.1 ◽

2010 ◽

Vol 23 (9) ◽

pp. 2440-2449 ◽

Cited By ~ 1

Author(s):

B. Timbal ◽

R. Kounkou ◽

G. A. Mills

Keyword(s):

Climate Change ◽

Climate Models ◽

Weather Prediction ◽

First Century ◽

Climate Projections ◽

Cool Season ◽

Near Surface ◽

Impact Of Climate Change ◽

Twenty First Century ◽

The Impact

Abstract Anthropogenic climate change is likely to be felt most acutely through changes in the frequency of extreme meteorological events. However, quantifying the impact of climate change on these events is a challenge because the core of the climate change science relies on general circulation models to detail future climate projections, and many of these extreme events occur on small scales that are not resolved by climate models. This note describes an attempt to infer the impact of climate change on one particular type of extreme meteorological event—the cool-season tornadoes of southern Australia. The Australian Bureau of Meteorology predicts threat areas for cool-season tornadoes using fine-resolution numerical weather prediction model output to define areas where the buoyancy of a near-surface air parcel and the vertical wind shear each exceed specified thresholds. The diagnostic has been successfully adapted to coarser-resolution climate models and applied to simulations of the current climate, as well as future projections of the climate over southern Australia. Simulations of the late twentieth century are used to validate the models’ ability to reproduce the climatology of the risk of cool-season tornado formation by comparing these with similar computations based on historical reanalyses. Model biases are overcome by setting model specific thresholds to define the cool-season tornado risk. The diagnostic, applied to simulations of the twenty-first century, is then used to quantify the impact of the projected climate change on cool-season tornado risk. The sign of the response is consistent across all models: a decrease of the risk of formation during the twenty-first century is projected, driven by the thermodynamical response. The thermal response is modulated by the dynamical response, which varies between models. The projected decrease in tornadoes risk during the cool season is consistent with the projection of positive southern annular mode trends and the known influence of this mode of variability on interannual to intraseasonal time-scale variations in cool-season tornado occurrence.

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