Observed and Simulated Spring and Summer Dryness in the United States: The Impact of the Pacific Sea Surface Temperature and Beyond

AbstractMonthly tropical sea surface temperature (SST) data are used as predictors to make statistical forecasts of cold season (November–March) precipitation and temperature for the contiguous United States. Through the use of the combined-lead sea surface temperature (CLSST) model, predictive information is discovered not just in recent SSTs but also from SSTs up to 18 months prior. We find that CLSST cold season forecast anomaly correlation skill is higher than that of the North American Multimodel Ensemble (NMME) and the SEAS5 model from the European Centre for Medium-Range Weather Forecasts (ECMWF) when averaged over the United States for both precipitation and 2-m air temperature. The precipitation forecast skill obtained by CLSST in parts of the Intermountain West is of particular interest because of its implications for water resources. In those regions, CLSST dramatically improves the skill over that of the dynamical model ensembles, which can be attributed to a robust statistical response of precipitation in this region to SST anomalies from the previous year in the tropical Pacific.

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Large-scale anomalies in sea-surface temperature and air-sea fluxes during wind relaxation events off the United States West Coast in summer

Journal of Geophysical Research Oceans ◽

10.1002/2016jc012613 ◽

2017 ◽

Vol 122 (3) ◽

pp. 2574-2594 ◽

Cited By ~ 7

Author(s):

Kayla R. Flynn ◽

Melanie R. Fewings ◽

Christopher Gotschalk ◽

Kelly Lombardo

Keyword(s):

United States ◽

Surface Temperature ◽

Sea Surface Temperature ◽

West Coast ◽

Large Scale ◽

The United States ◽

Sea Surface

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Summer aridity in the United States: Response to mid-Holocene changes in insolation and sea surface temperature

Geophysical Research Letters ◽

10.1029/2006gl028012 ◽

2006 ◽

Vol 33 (22) ◽

Cited By ~ 59

Author(s):

Noah S. Diffenbaugh ◽

Moetasim Ashfaq ◽

Bryan Shuman ◽

John W. Williams ◽

Patrick J. Bartlein

Keyword(s):

United States ◽

Surface Temperature ◽

Sea Surface Temperature ◽

The United States ◽

Sea Surface

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Impact of Sea Surface Temperature and Soil Moisture on Summer Precipitation in the United States Based on Observational Data

Journal of Hydrometeorology ◽

10.1175/2011jhm1312.1 ◽

2011 ◽

Vol 12 (5) ◽

pp. 1086-1099 ◽

Cited By ~ 35

Author(s):

Rui Mei ◽

Guiling Wang

Keyword(s):

United States ◽

Soil Moisture ◽

Correlation Analysis ◽

Surface Temperature ◽

Precipitation Amount ◽

Summer Precipitation ◽

The United States ◽

Sea Surface ◽

Precipitation Prediction ◽

The Impact

Abstract This study examines the impact of sea surface temperature (SST) and soil moisture on summer precipitation over two regions of the United States (the upper Mississippi River basin and the Great Plains) based on data from observation and observation-forced model simulations (in the case of soil moisture). Results from SST–precipitation correlation analysis show that spatially averaged SST of identified oceanic areas are better predictors than derived SST patterns from the EOF analysis and that both predictors are strongly associated with the Pacific Ocean. Results from conditioned soil moisture–precipitation correlation analysis show that the impact of soil moisture on precipitation differs between the outer-quartiles years (with summer precipitation amount in the first and fourth quartiles) and inner-quartiles years (with summer precipitation amount in the second and third quartiles), and also between the high- and low-skill SST years (categorized according to the skill of SST-based precipitation prediction). Specifically, the soil moisture–precipitation feedback is more likely to be positive and significant in the outer-quartiles years and in the years when the skill of precipitation prediction based on SST alone is low. This study indicates that soil moisture should be included as a useful predictor in precipitation prediction, and the resulting improvement in prediction skills will be especially substantial during years of large precipitation anomalies. It also demonstrates the complexity of the impact of SST and soil moisture on precipitation, and underlines the important complementary roles both SST and soil moisture play in determining precipitation.

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North American April tornado occurrences linked to global sea surface temperature anomalies

Science Advances ◽

10.1126/sciadv.aaw9950 ◽

2019 ◽

Vol 5 (8) ◽

pp. eaaw9950 ◽

Cited By ~ 1

Author(s):

J.-E. Chu ◽

A. Timmermann ◽

J.-Y. Lee

Keyword(s):

United States ◽

Surface Temperature ◽

Sea Surface Temperature ◽

North American ◽

General Circulation ◽

Large Scale ◽

Moisture Flux ◽

General Circulation Models ◽

The United States ◽

Sea Surface

Annual tornado occurrences over North America display large interannual variability and a statistical linkage to sea surface temperature (SST) anomalies. However, the underlying physical mechanisms for this connection and its modulation in a rapidly varying seasonal environment still remain elusive. Using tornado data over the United States from 1954 to 2016 in combination with SST-forced atmospheric general circulation models, we show a robust dynamical linkage between global SST conditions in April, the emergence of the Pacific-North American teleconnection pattern (PNA), and the year-to-year tornado activity in the Southern Great Plains (SGP) region of the United States. Contrasting previous studies, we find that only in April SST-driven atmospheric circulation anomalies can effectively control the northward moisture-laden flow from the Gulf of Mexico, boosting low-level moisture flux convergence over the SGP. These strong large-scale connections are absent in other months because of the strong seasonality of the PNA and background moisture conditions.

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Interannual Variability and Trends in Sea Surface Temperature, Lower and Middle Atmosphere Temperature at Different Latitudes for 1980–2019

Atmosphere ◽

10.3390/atmos12040454 ◽

2021 ◽

Vol 12 (4) ◽

pp. 454

Author(s):

Andrew R. Jakovlev ◽

Sergei P. Smyshlyaev ◽

Vener Y. Galin

Keyword(s):

Surface Temperature ◽

Sea Surface Temperature ◽

Lower Stratosphere ◽

Middle Atmosphere ◽

Southern Oscillation ◽

Lower Troposphere ◽

Reanalysis Data ◽

Sea Surface ◽

The Arctic ◽

The Impact

The influence of sea-surface temperature (SST) on the lower troposphere and lower stratosphere temperature in the tropical, middle, and polar latitudes is studied for 1980–2019 based on the MERRA2, ERA5, and Met Office reanalysis data, and numerical modeling with a chemistry-climate model (CCM) of the lower and middle atmosphere. The variability of SST is analyzed according to Met Office and ERA5 data, while the variability of atmospheric temperature is investigated according to MERRA2 and ERA5 data. Analysis of sea surface temperature trends based on reanalysis data revealed that a significant positive SST trend of about 0.1 degrees per decade is observed over the globe. In the middle latitudes of the Northern Hemisphere, the trend (about 0.2 degrees per decade) is 2 times higher than the global average, and 5 times higher than in the Southern Hemisphere (about 0.04 degrees per decade). At polar latitudes, opposite SST trends are observed in the Arctic (positive) and Antarctic (negative). The impact of the El Niño Southern Oscillation phenomenon on the temperature of the lower and middle atmosphere in the middle and polar latitudes of the Northern and Southern Hemispheres is discussed. To assess the relative influence of SST, CO2, and other greenhouse gases’ variability on the temperature of the lower troposphere and lower stratosphere, numerical calculations with a CCM were performed for several scenarios of accounting for the SST and carbon dioxide variability. The results of numerical experiments with a CCM demonstrated that the influence of SST prevails in the troposphere, while for the stratosphere, an increase in the CO2 content plays the most important role.

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