European winter precipitation extremes and large-scale circulation: a coupled model and its scenarios

Abstract:This study presents an analysis of daily temperature and precipitation extremes with return periods ranging from 2 to 50 years in the Coupled Model Intercomparison Project Phase 6 (CMIP6) multi-model ensemble of simulations. Judged by similarity with reanalyses, the new-generation models simulate the present-day temperature and precipitation extremes reasonably well. In line with previous CMIP simulations, the new simulations continue to project a large-scale picture of more frequent and more intense hot temperature extremes and precipitation extremes and vanishing cold extremes under continued global warming. Changes in temperature extremes outpace changes in global annual mean surface air temperature (GSAT) over most land masses, while changes in precipitation extremes follow changes in GSAT globally at roughly the Clausius-Clapeyron rate of ∼7%/°C. Changes in temperature and precipitation extremes normalized with respect to GSAT do not depend strongly on the choice of forcing scenario or model climate sensitivity, and do not vary strongly over time, but with notable regional variations. Over the majority of land regions, the projected intensity increases and relative frequency increases tend to be larger for more extreme hot temperature and precipitation events than for weaker events. To obtain robust estimates of these changes at local scales, large initial-condition ensemble simulations are needed. Appropriate spatial pooling of data from neighboring grid cells within individual simulations can, to some extent, reduce the needed ensemble size.

Download Full-text

Contribution of large-scale circulation anomalies to variability of summer precipitation extremes in northeast China

Atmospheric Science Letters ◽

10.1002/asl.867 ◽

2018 ◽

Vol 19 (12) ◽

pp. e867 ◽

Cited By ~ 4

Author(s):

Fuqiang Cao ◽

Tao Gao ◽

Li Dan ◽

Zhuguo Ma ◽

Xiujing Yang ◽

...

Keyword(s):

Northeast China ◽

Large Scale ◽

Summer Precipitation ◽

Precipitation Extremes ◽

Large Scale Circulation ◽

Circulation Anomalies

Download Full-text

Precipitation and Moisture in Four Leading CMIP5 Models: Biases across Large-Scale Circulation Regimes and Their Attribution to Dynamic and Thermodynamic Factors

Journal of Climate ◽

10.1175/jcli-d-17-0718.1 ◽

2018 ◽

Vol 31 (13) ◽

pp. 5089-5106 ◽

Cited By ~ 3

Author(s):

Mengmiao Yang ◽

Guang J. Zhang ◽

De-Zheng Sun

Keyword(s):

General Circulation ◽

Large Scale ◽

Coupled Model ◽

General Circulation Models ◽

Cmip5 Models ◽

Frequency Of Occurrence ◽

Upward Motion ◽

Large Scale Circulation ◽

Intercomparison Project ◽

Strong Upward Motion

As key variables in general circulation models, precipitation and moisture in four leading models from CMIP5 (phase 5 of the Coupled Model Intercomparison Project) are analyzed, with a focus on four tropical oceanic regions. It is found that precipitation in these models is overestimated in most areas. However, moisture bias has large intermodel differences. The model biases in precipitation and moisture are further examined in conjunction with large-scale circulation by regime-sorting analysis. Results show that all models consistently overestimate the frequency of occurrence of strong upward motion regimes and peak descending regimes of 500-hPa vertical velocity [Formula: see text]. In a given [Formula: see text] regime, models produce too much precipitation compared to observation and reanalysis. But for moisture, their biases differ from model to model and also from level to level. Furthermore, error causes are revealed through decomposing contribution biases into dynamic and thermodynamic components. For precipitation, the contribution errors in strong upward motion regimes are attributed to the overly frequent [Formula: see text]. In the weak upward motion regime, the biases in the dependence of precipitation on [Formula: see text] and the [Formula: see text] probability density function (PDF) make comparable contributions, but often of opposite signs. On the other hand, the biases in column-integrated water vapor contribution are mainly due to errors in the frequency of occurrence of [Formula: see text], while thermodynamic components contribute little. These findings suggest that errors in the frequency of [Formula: see text] occurrence are a significant cause of biases in the precipitation and moisture simulation.

Download Full-text

Changes in the winter precipitation in Romania and its relation to the large-scale circulation

Tellus A Dynamic Meteorology and Oceanography ◽

10.1034/j.1600-0870.1996.t01-3-00004.x ◽

1996 ◽

Vol 48 (4) ◽

pp. 538-552 ◽

Cited By ~ 60

Author(s):

ARISTITA BUSUIOC ◽

HANS VON STORCH

Keyword(s):

Large Scale ◽

Winter Precipitation ◽

Large Scale Circulation

Download Full-text

Characteristics of Large-Scale Circulation Affecting the Inter-Annual Precipitation Variability in Northern Sumatra Island during Boreal Summer

Atmosphere ◽

10.3390/atmos12020136 ◽

2021 ◽

Vol 12 (2) ◽

pp. 136

Author(s):

Yahya Darmawan ◽

Huang-Hsiung Hsu ◽

Jia-Yuh Yu

Keyword(s):

Large Scale ◽

Precipitation Variability ◽

Specific Humidity ◽

Boreal Summer ◽

Moisture Budget ◽

Large Scale Circulation ◽

Budget Analysis ◽

Sumatra Island ◽

Precipitation Anomalies ◽

The Impact

This study aims to explore the contrasting characteristics of large-scale circulation that led to the precipitation anomalies over the northern parts of Sumatra Island. Further, the impact of varying the Asian–Australian Monsoon (AAM) was investigated for triggering the precipitation variability over the study area. The moisture budget analysis was applied to quantify the most dominant component that induces precipitation variability during the JJA (June, July, and August) period. Then, the composite analysis and statistical approach were applied to confirm the result of the moisture budget. Using the European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Anaysis Interim (ERA-Interim) from 1981 to 2016, we identified 9 (nine) dry and 6 (six) wet years based on precipitation anomalies, respectively. The dry years (wet years) anomalies over the study area were mostly supported by downward (upward) vertical velocity anomaly instead of other variables such as specific humidity, horizontal velocity, and evaporation. In the dry years (wet years), there is a strengthening (weakening) of the descent motion, which triggers a reduction (increase) of convection over the study area. The overall downward (upward) motion of westerly (easterly) winds appears to suppress (support) the convection and lead to negative (positive) precipitation anomaly in the whole region but with the largest anomaly over northern parts of Sumatra. The AAM variability proven has a significant role in the precipitation variability over the study area. A teleconnection between the AAM and other global circulations implies the precipitation variability over the northern part of Sumatra Island as a regional phenomenon. The large-scale tropical circulation is possibly related to the PWC modulation (Pacific Walker Circulation).

Download Full-text

Impact of air–sea coupling on the climate change signal over the Iberian Peninsula

Climate Dynamics ◽

10.1007/s00382-021-05812-x ◽

2021 ◽

Author(s):

Alba de la Vara ◽

William Cabos ◽

Dmitry V. Sein ◽

Claas Teichmann ◽

Daniela Jacob

Keyword(s):

Climate Change ◽

Iberian Peninsula ◽

Mediterranean Sea ◽

Large Scale ◽

Regional Distribution ◽

Coupled Model ◽

Climate Change Signal ◽

The North ◽

The Mediterranean ◽

The Impact

AbstractIn this work we use a regional atmosphere–ocean coupled model (RAOCM) and its stand-alone atmospheric component to gain insight into the impact of atmosphere–ocean coupling on the climate change signal over the Iberian Peninsula (IP). The IP climate is influenced by both the Atlantic Ocean and the Mediterranean sea. Complex interactions with the orography take place there and high-resolution models are required to realistically reproduce its current and future climate. We find that under the RCP8.5 scenario, the generalized 2-m air temperature (T2M) increase by the end of the twenty-first century (2070–2099) in the atmospheric-only simulation is tempered by the coupling. The impact of coupling is specially seen in summer, when the warming is stronger. Precipitation shows regionally-dependent changes in winter, whilst a drier climate is found in summer. The coupling generally reduces the magnitude of the changes. Differences in T2M and precipitation between the coupled and uncoupled simulations are caused by changes in the Atlantic large-scale circulation and in the Mediterranean Sea. Additionally, the differences in projected changes of T2M and precipitation with the RAOCM under the RCP8.5 and RCP4.5 scenarios are tackled. Results show that in winter and summer T2M increases less and precipitation changes are of a smaller magnitude with the RCP4.5. Whilst in summer changes present a similar regional distribution in both runs, in winter there are some differences in the NW of the IP due to differences in the North Atlantic circulation. The differences in the climate change signal from the RAOCM and the driving Global Coupled Model show that regionalization has an effect in terms of higher resolution over the land and ocean.

Download Full-text