Article
Environmental Sciences
Nicola Maher, Jennifer E. Kay, Antonietta Capotondi
Summary: This study reveals the significant impact of the Pacific Decadal Oscillation (PDO) on the temperature and precipitation teleconnections of El Nino Southern Oscillation (ENSO) events over North America, with positive PDO enhancing El Nino teleconnections and diminishing La Nina teleconnections.
ENVIRONMENTAL RESEARCH LETTERS
(2022)
Article
Geography, Physical
Ioana C. Stefanescu, Bryan N. Shuman, Laurie D. Grigg, Adriana Bailey, Vania Stefanova, W. Wyatt Oswald
Summary: In eastern North America, an increase in annual precipitation during the Holocene resulted in higher lake levels and a transformation of ecosystems. The isotopic composition of leaf-wax n-alkanes can be used to reconstruct past precipitation dynamics. However, changes in moisture sources and precipitation patterns can complicate the interpretation of isotopic records.
QUATERNARY SCIENCE REVIEWS
(2023)
Article
Environmental Sciences
Yao Ge, Dehai Luo
Summary: This study reveals that the decadal variability of winter cold extremes over eastern North America is mainly influenced by the Pacific decadal oscillation (PDO), while their interannual variability is primarily regulated by the Victoria mode (VM). A positive PDO promotes cold extremes in the lower latitudes, while a positive VM leads to intense cold extremes in the higher latitudes. These new findings help us understand the origins of the interannual-decadal variability of winter cold extremes over eastern North America.
ENVIRONMENTAL RESEARCH LETTERS
(2023)
Article
Geography, Physical
Helen Mackay, Matthew J. Amesbury, Pete G. Langdon, Dan J. Charman, Gabriel Magnan, Simon van Bellen, Michelle Garneau, Rupert Bainbridge, Paul D. M. Hughes
Summary: The study reconstructs hydroclimatic changes in northeastern North America over the past millennium, revealing spatially divergent patterns during the Medieval Climate Anomaly and Little Ice Age. The wetter conditions in southern peatlands and drier conditions in northern and continental sites during these periods suggest complex hydroclimatic patterns. The spatial variability of hydroclimate change during the Little Ice Age may be related to local permafrost aggradation and similarities with dry periods during the Medieval Climate Anomaly.
QUATERNARY SCIENCE REVIEWS
(2021)
Article
Meteorology & Atmospheric Sciences
Jonathan D. Beverley, Matthew Collins, F. Hugo Lambert, Robin Chadwick
Summary: Research suggests that future changes to the positive-phase ENSO teleconnection to the North Pacific/North America sector will weaken, largely due to anomalous circulation changes over the North Pacific. The study also indicates that changes in forcing from equatorial central Pacific precipitation anomalies are more significant than changes in the global basic state background circulation.
JOURNAL OF CLIMATE
(2021)
Article
Geosciences, Multidisciplinary
Eunsang Cho, Rachel R. McCrary, Jennifer M. Jacobs
Summary: Projected changes in extreme snow-related indicators show decreases in the continental US and southern Canada, but increases in Alaska and northern Canada by the late 21st century. California and the Pacific Northwest are expected to experience an increase in extreme runoff potential, potentially leading to larger rain-on-snow floods. Regions with high variability among model ensembles need further investigation to reduce regional uncertainties.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Environmental Sciences
Sanjiv Kumar, Candida F. Dewes, Matthew Newman, Yanan Duan
Summary: Adaptation planning for climate change requires a comprehensive understanding of hydroclimate variability and predictability. Using large ensemble data sets, we quantify the projected change in land hydroclimate variability and its predictability. We find that while global warming intensifies El Nino-Southern Oscillation (ENSO) and its associated precipitation variability, the corresponding change in soil moisture variability is relatively small or even decreases due to the concurrent reduction in land surface memory. Regional mean state changes in land surface (soil moisture) primarily drive future drought and pluvial risks, suggesting that infrastructure planning can incorporate robust mean state changes despite uncertainties in variability projections. In regions where the ENSO signal increases, we observe a shift in the frequency of drought and pluvial events, with higher power on inter-annual time scales but less power on decadal time scales, enhancing inter-annual hydroclimate predictability.
Article
Environmental Sciences
Zhicong Yin, Yu Wan, Huijun Wang
Summary: This study explores the interannual relationship between O-3 pollution and late-spring snow cover in West Siberia. It shows that changes in snow cover and meteorological conditions around the mid-1990s significantly impact O-3 concentrations in North China.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2021)
Article
Environmental Sciences
Laura Perez, Marcelo Barreiro, Ismael Etchevers, Carolina Crisci, Felipe Garcia-Rodriguez
Summary: The study of RdlP mud depocenter revealed that centennial hydrological and proxy variability is mainly modulated by climate variability modes. The increase in agricultural activities, particularly soy bean cultivation, combined with intensified rainfall and runoff, led to higher continental input and marine productivity changes, affecting soil erosion and sediment transport, with the final fate being the RdlP mud depocenter.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Meteorology & Atmospheric Sciences
Shinji Matsumura, Takeshi Horinouchi
Summary: The East Asian summer climate has undergone significant changes since the late 1990s, primarily due to a weakening of the Pacific-Japan (PJ) teleconnection pattern that previously influenced precipitation variability in the region. However, western Japan has experienced frequent heavy rainfall events in recent years. Analysis of atmospheric data and observations from 1979 to 2020 indicates that summer precipitation has increased the most in Japan, particularly in the Southwest Islands, where cumulus convection has become more dominant in driving precipitation variability. This shift in precipitation variability is closely related to the second precipitation mode in East Asia, which has replaced the PJ pattern as a leading driver of precipitation variability in western Japan.
JOURNAL OF CLIMATE
(2023)
Article
Geosciences, Multidisciplinary
C. J. Batchelor, S. A. Marcott, I. J. Orland, F. He, R. L. Edwards
Summary: The connection between abrupt high-latitude warming during the last glacial period-Dansgaard-Oeschger (DO) events-and rapid climate changes at lower latitudes has revealed inter-hemispheric teleconnections in the ocean-atmosphere system. We examined a speleothem in Wisconsin that grew from 70-50 thousand years ago and found large negative oxygen isotope (δO-18) excursions that correlate with DO events recorded in the ice core of the North Greenland Ice Core Project. Climate simulations suggest that abrupt DO warming would increase the δO-18 of annual precipitation in the study area, supporting the observed negative δO-18 excursions.
Article
Geosciences, Multidisciplinary
Mathieu A. Poupon, Laure Resplandy, Marina Levy, Laurent Bopp
Summary: Observations suggest that the tropical Pacific Ocean has experienced oxygen loss and expansion of its oxygen minimum zone since the 1960s. The attribution of this phenomenon to anthropogenic forcing is challenging due to limited data availability and natural variability introduced by the Pacific Decadal Oscillation (PDO). Using observations and hindcast simulations from two global ocean circulation models, it is found that the PDO influences oxygen dynamics and OMZ extent in the tropical Pacific. However, the separation of anthropogenic trend from natural variations is hindered by the incomplete coverage of observations.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Multidisciplinary Sciences
Jeffrey S. Pigati, Kathleen B. Springer
Summary: The Younger Dryas is a prime example of abrupt climate change in recent geologic history. Research has revealed that this climate event occurred in two distinct stages and had spatially complex conditions. The study also found that even short-lived changes in the Atlantic Meridional Overturning Circulation can have profound consequences for ecosystems worldwide.
SCIENTIFIC REPORTS
(2022)
Article
Meteorology & Atmospheric Sciences
Roberto Suarez-Moreno, Yochanan Kushnir, Richard Seager
Summary: Utilizing canonical correlation analysis, it was found that the North Atlantic Oscillation is the primary driver of Mediterranean hydroclimate variability, while the decadal variability of Atlantic-Mediterranean sea surface temperatures influences the NAO-induced hydroclimate response. Additionally, anthropogenic global sea surface temperature warming is robustly linked with increased surface air temperatures in the Mediterranean region.
Article
Meteorology & Atmospheric Sciences
Alejandro Builes-Jaramillo, Juliana Valencia, Hernan D. Salas
Summary: This study investigates the influence of the transitions between ENSO phases on the general circulation and three Low-Level Jets (LLJs) over northern South America. It is found that these transitions affect the vertical wind speeds associated with the Walker cells over the far-eastern Pacific Ocean, leading to changes in the downward and upward velocities over northern South America. Additionally, the transitions also impact the low-level water vapor transport and precipitation patterns in the Caribbean LLJ, Orinoco LLJ, and Chocojet.
ATMOSPHERIC RESEARCH
(2023)
Article
Multidisciplinary Sciences
Hiroyuki Murakami, Thomas L. Delworth, William F. Cooke, Ming Zhao, Baoqiang Xiang, Pang-Chi Hsu
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2020)
Article
Geosciences, Multidisciplinary
Mitchell Bushuk, Michael Winton, David B. Bonan, Edward Blanchard-Wrigglesworth, Thomas L. Delworth
GEOPHYSICAL RESEARCH LETTERS
(2020)
Article
Geosciences, Multidisciplinary
Kai-Chih Tseng, Nathaniel C. Johnson, Sarah B. Kapnick, Thomas L. Delworth, Feiyu Lu, William Cooke, Andrew T. Wittenberg, Anthony J. Rosati, Liping Zhang, Colleen McHugh, Xiaosong Yang, Matthew Harrison, Fanrong Zeng, Gan Zhang, Hiroyuki Murakami, Mitchell Bushuk, Liwei Jia
Summary: Atmospheric rivers play a significant role in determining water supply and can lead to extreme precipitation hazards. Current research mainly focuses on subseasonal prediction, with limited efforts for multiseasonal prediction. This study demonstrates the potential of multiseasonal AR frequency forecasts with predictive skills up to 9 months in advance.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Environmental Sciences
Sarah K. Weidman, Thomas L. Delworth, Sarah B. Kapnick, William F. Cooke
Summary: The study shows that anthropogenic radiative forcing increased the likelihood of the extreme heat event in Alaska in 2019 by 6%, and that the probability of similar events in the future is likely to substantially increase. Some models project that by 2090, the likelihood of such events exceeding 75% with rapidly increasing levels of greenhouse gases.
Article
Meteorology & Atmospheric Sciences
Xiaosong Yang, Thomas L. Delworth, Fanrong Zeng, Liping Zhang, William F. Cooke, Matthew J. Harrison, Anthony Rosati, Seth Underwood, Gilbert P. Compo, Chesley McColl
Summary: The study developed a decadal coupled reanalysis/initialization system using GFDL's new coupled model SPEAR, which significantly improved the model's prediction skill by restoring atmospheric parameters to observations. Results showed that different initialization approaches and atmospheric forcings had an impact on the prediction, with SPEAR model demonstrating superior performance in predicting multi-decadal trends and North Atlantic subpolar gyre SST.
JOURNAL OF ADVANCES IN MODELING EARTH SYSTEMS
(2021)
Article
Meteorology & Atmospheric Sciences
Gan Zhang, Hiroyuki Murakami, William F. Cooke, Zhuo Wang, Liwei Jia, Feiyu Lu, Xiaosong Yang, Thomas L. Delworth, Andrew T. Wittenberg, Matthew J. Harrison, Mitchell Bushuk, Colleen McHugh, Nathaniel C. Johnson, Sarah B. Kapnick, Kai-Chih Tseng, Liping Zhang
Summary: This study demonstrates the potential predictability of seasonal variations of baroclinic wave activity (BWA) by analyzing a large ensemble of climate simulations forced by observed sea surface temperatures (SSTs). The analysis identifies both well-known and unfamiliar BWA responses to SST forcings and confirms the model-indicated predictability of BWA. Leveraging identified SST-BWA relationships can help improve skillful predictions of BWA in operational seasonal prediction systems, extending long-range predictions of the statistics of extratropical weather events and their impacts.
NPJ CLIMATE AND ATMOSPHERIC SCIENCE
(2021)
Article
Environmental Sciences
H. Murakmai, T. L. Delworth, W. F. Cooke, S. B. Kapnick, P. -C. Hsu
Summary: The frequency of large-scale anomalous precipitation events associated with heavy precipitation has been increasing in Japan, and this increase is not solely due to internal variability but also influenced by anthropogenic forcing. Such events are expected to continue increasing in the future, posing a challenge for climate mitigation.
Article
Meteorology & Atmospheric Sciences
Kai-Chih Tseng, Nathaniel C. Johnson, Sarah B. Kapnick, William Cooke, Thomas L. Delworth, Liwei Jia, Feiyu Lu, Colleen McHugh, Hiroyuki Murakami, Anthony J. Rosati, Andrew T. Wittenberg, Xiaosong Yang, Fanrong Zeng, Liping Zhang
Summary: Quantifying the response of atmospheric rivers to radiative forcing is challenging due to uncertainties caused by internal climate variability, differences in shared socioeconomic pathways, and methods used in AR detection algorithms. However, this study found that, under both moderate and high emissions scenarios, increases in AR-day frequency emerge from the noise of internal variability by 2060. This signal is robust across different SSPs and time-independent detection criteria.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2022)
Article
Meteorology & Atmospheric Sciences
Youngji Joh, Thomas L. Delworth, Andrew T. Wittenberg, William F. Cooke, Anthony J. Rosati, Liping Zhang
Summary: Understanding the behavior of western boundary current systems is crucial for predicting biogeochemical cycles, fisheries, and regional climate patterns in midlatitude oceans. Using a global coupled climate model, this study shows that increasing greenhouse gases lead to changes in the time scale of the Kuroshio Extension sea surface height variability, with a shift towards longer time scales.
NPJ CLIMATE AND ATMOSPHERIC SCIENCE
(2022)
Article
Meteorology & Atmospheric Sciences
Baoqiang Xiang, Bin Wang, Wei Zhang, Lucas Harris, Thomas L. Delworth, Gan Zhang, William F. Cooke
Summary: This study reveals three localized atmospheric circulation modes that significantly influence the subseasonal variation of tropical cyclone activity, impacting precipitation, cyclone genesis, intensity, track, and landfall near the U.S. coast.
NPJ CLIMATE AND ATMOSPHERIC SCIENCE
(2022)
Article
Multidisciplinary Sciences
Thomas L. Delworth, William F. Cooke, Vaishali Naik, David Paynter, Liping Zhang
Summary: The study reveals that while the decline in summer rainfall in the Mediterranean region can be reversed with greenhouse gas reductions, the winter rainfall decline continues due to the weakening of the Atlantic Meridional Overturning Circulation (AMOC). This unexpected finding could complicate the recovery of Mediterranean climate change.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Meteorology & Atmospheric Sciences
Bor-Ting Jong, Thomas L. Delworth, William F. Cooke, Kai-Chih Tseng, Hiroyuki Murakami
Summary: High-resolution global climate models accurately simulate extreme precipitation events in the Northeastern United States. Future projections indicate that unprecedented rainfall events may occur in the region by the mid-21st century, driven by increasing anthropogenic radiative forcing.
NPJ CLIMATE AND ATMOSPHERIC SCIENCE
(2023)
Article
Meteorology & Atmospheric Sciences
Youngji Joh, Thomas L. Delworth, Andrew T. Wittenberg, Xiaosong Yang, Anthony Rosati, Nathaniel C. Johnson, Liwei Jia
Summary: Using satellite observations and reanalysis datasets, this study finds that the variations in heat flux in the Kuroshio-Oyashio Extension (KOE) are closely linked to sea surface height (SSH) variability in the Kuroshio Extension (KE) in both seasonal and decadal time scales. The anomalies in oceanic and atmospheric conditions associated with anomalous KE upper-ocean temperature lead to significant heat transfer from the ocean to the atmosphere during November-December-January (NDJ). These NDJ KOE heat flux variations have recently become stronger and are associated with enhanced KE decadal variability. This study highlights the role of KOE heat fluxes as a communicator between the upper-ocean and the overlying atmosphere and suggests that they could be a useful North Pacific climate indicator.
NPJ CLIMATE AND ATMOSPHERIC SCIENCE
(2023)
Article
Environmental Sciences
Liping Zhang, Thomas L. Delworth, Xiaosong Yang, Fanrong Zeng
Summary: Long-term sea-level rise and multiyear to decadal variations in sea level along the US East Coast can be skillfully predicted using observations and climate model predictions, with greenhouse gas warming and variations in the Atlantic Meridional Overturning Circulation playing significant roles.
COMMUNICATIONS EARTH & ENVIRONMENT
(2023)
Article
Environmental Sciences
Liping Zhang, Thomas L. Delworth, Xiaosong Yang, Fanrong Zeng, Feiyu Lu, Yushi Morioka, Mitchell Bushuk
Summary: This study investigates the causes of low Antarctic sea ice extent using a coupled climate model partially constrained by observations. It finds that the subsurface Southern Ocean plays a critical role in the persistence of negative sea ice anomalies over 2016-2021, with the warming and destabilization of the ocean reducing sea ice extent over several years. The simultaneous variations in the atmosphere and ocean after 2016 further amplify the decline in Antarctic sea ice extent.
COMMUNICATIONS EARTH & ENVIRONMENT
(2022)