A5057805502- Climate variability and models
- Oceanographic and Atmospheric Processes
- Meteorological Phenomena and Simulations
- Tropical and Extratropical Cyclones Research
- Atmospheric and Environmental Gas Dynamics
- Marine and coastal ecosystems
- Geology and Paleoclimatology Research
- Atmospheric chemistry and aerosols
- Ocean Waves and Remote Sensing
- Atmospheric Ozone and Climate
- Air Quality and Health Impacts
- Species Distribution and Climate Change
- Wind and Air Flow Studies
- Climate Change and Health Impacts
- Fire effects on ecosystems
- Cryospheric studies and observations
- Climate change impacts on agriculture
- Climate Change Policy and Economics
- Methane Hydrates and Related Phenomena
- Fault Detection and Control Systems
- Ecosystem dynamics and resilience
- Hydrological Forecasting Using AI
- Urban Heat Island Mitigation
- Ocean Acidification Effects and Responses
- Environmental Monitoring and Data Management
University of Wisconsin–Madison
2014-2025
Cooperative Institute for Research in Environmental Sciences
2019-2020
University of Colorado Boulder
2019-2020
NOAA Physical Sciences Laboratory
2020
NOAA Earth System Research Laboratory
2019
University of Washington
2002-2019
University of Miami
2018-2019
University of Hawaiʻi at Mānoa
2016
Cooperative Institute for Climate and Satellites
2007
Gonzaga University
1995
Abstract The Pacific decadal oscillation (PDO), the dominant year-round pattern of monthly North sea surface temperature (SST) variability, is an important target ongoing research within meteorological and climate dynamics communities central to work many geologists, ecologists, natural resource managers, social scientists. Research over last 15 years has led emerging consensus: PDO not a single phenomenon, but instead result combination different physical processes, including both remote...
Abstract From observational analysis a Pacific mode of variability in the intertropical convergence zone (ITCZ)/cold tongue region is identified that possesses characteristics and interpretation similar to dominant “meridional” interannual–decadal tropical Atlantic. The Atlantic meridional modes are characterized by an anomalous sea surface temperature (SST) gradient across mean latitude ITCZ coupled displacement toward warmer hemisphere. Both forced trade wind variations their respective...
Midlatitude atmospheric variability is identified as a particularly effective component of the stochastic forcing ENSO. This realized via seasonal footprinting mechanism (SFM), in which tropical atmosphere forced during spring and summer by SST anomalies generated midlatitude previous winter. The strong relationship between SFM ENSO may serve to enhance predictability supports view that linearly stable nature.
A connection between the mid‐latitude and tropical Pacific is identified in a coupled general circulation model (CGCM). The involves seasonal coupling winter atmospheric anomalies, summer equatorial wind stress anomalies. results from “footprinting” mechanism, which atmosphere responds to subtropical sea surface temperature (SST) anomalies that are generated by variability during previous winter. Details of connection, footprinting mechanism presented. Implications for interannual ENSO...
El Niño events typically lead to delayed rainfall and decreased rice planting in Indonesia's main rice-growing regions, thus prolonging the hungry season increasing risk of annual deficits. Here we use a assessment framework examine potential impact natural variability on agriculture 2050 under conditions climate change, with focus two rice-producing areas: Java Bali. We select 30-day delay monsoon onset as threshold beyond which significant country's economy is likely occur. To project...
Recently documented trends in the existing records of hurricane intensity and their relationship to increasing sea surface temperatures suggest that may be due global warming. However, it is presently being argued are too inconsistent accurately measure trends. As a first step addressing this debate, we constructed more homogeneous record found previously some ocean basins well supported, but others contain inflated or spurious.
We present intriguing evidence that the majority of El Niño events over past four decades are preceded by a distinctive sea‐surface warming and southwesterly wind anomaly in vicinity Intertropical Convergence Zone (ITCZ) during boreal spring. This phenomenon, known as Meridional Mode (MM), is shown to be intrinsic thermodynamic coupling between atmosphere ocean. The MM effectively acts conduit through which extratropical influences ENSO. Modeling results further suggest plays vital role...
Connections between the Atlantic Meridional Mode (AMM) and seasonal hurricane activity are investigated. The AMM, a dynamical “mode” of variability intrinsic to tropical coupled ocean‐atmosphere system, is strongly related on both decadal interannual time scales. connection arises due AMM's relationship with number local climatic conditions that all cooperate in their influence activity. Further analysis indicates Multi‐decadal Oscillation (AMO) can excite AMM As such, it suggested AMO's...
Climate variability in the tropical Pacific affects global climate on a wide range of time scales. On interannual scales, is home to El Niño–Southern Oscillation (ENSO). Decadal variations and changes Pacific, referred here collectively as decadal (TPDV), also profoundly affect system. Here, we use TPDV refer any form or change that occurs atmosphere, ocean, over land within Pacific. “Decadal,” which broad sense encompass multiyear through multidecadal includes about mean state externally...
Atlantic hurricane variability on decadal and interannual time scales is reconsidered in a framework based leading mode of coupled ocean-atmosphere known as the meridional (AMM). It shown that large part overall “hurricane activity,” which depends number storms season, their duration, intensity, can be explained by systematic shifts cyclogenesis regions. These are strongly correlated with AMM well multidecadal scales. suggested serves to unify previously documented relationships between...
The International Satellite Cloud Climatology Project (ISCCP) multi‐decadal record of cloudiness exhibits a well‐known global decrease in cloud amounts. This downward trend has recently been used to suggest widespread increases surface solar heating, decreases planetary albedo, and deficiencies climate models. Here we show that trends observed the ISCCP data are satellite viewing geometry artifacts not related physical changes atmosphere. Our results its current form, may be appropriate for...
Abstract Previous studies suggest that extratropical atmospheric variability influences the tropics via seasonal footprinting mechanism (SFM), in which fluctuations North Pacific Oscillation (NPO) impact ocean surface heat fluxes during winter and resulting springtime subtropical SST anomalies alter atmosphere–ocean system over following summer, fall, winter. Here, authors test SFM hypothesis by imposing NPO-related flux forcing an GCM coupled to a reduced gravity model slab extratropics....
An influence of midlatitude atmospheric variability on interannual ENSO and decadal ENSO-like is established investigated in the Commonwealth Scientific Industrial Research Organisation (CSIRO) coupled general circulation models (CGCMs). The effect felt Tropics via previously hypothesized “seasonal footprinting mechanism” (SFM), which a tropical forced during spring summer by SST anomalies that are generated previous winter. includes equatorial zonal wind stress act as stochastic forcing for...
Dust in the Wind The temperature of North Atlantic surface waters has a major effect on climate variety ways, not least because its heat content helps to control hurricane formation and strength. warmed considerably recent decades, trend generally associated with global or regional air increases, changes ocean circulation. Evan et al. (p. 778 , published online 26 March) use nearly 30 years satellite data examine another source variability, radiative effects atmospheric aerosols. Low...
Central Pacific (CP)-type and Eastern (EP)-type El Niño the Southern Oscillation (ENSO) events are investigated using linear inverse modeling. Optimal initial conditions growth rates for CP or EP ENSO identified explicitly a norm. The dominant difference in that lead to is role of second empirical orthogonal function tropical sea surface temperature, which represents Meridional Mode (PMM). CP-type include warm SST anomalies central subtropical (a characteristic PMM) while optimal EP-type...
Anthropogenic climate change is altering ecological and human systems globally, including in United States (US) national parks, which conserve unique biodiversity resources. Yet, the magnitude spatial patterns of across all parks have been unknown. Here, first analysis historical projected temperature precipitation 417 US we show that exposes park area more than as a whole. This occurs because extensive parts are Arctic, at high elevations, or arid southwestern US. Between 1895 2010, mean...
Abstract A defining feature of Pacific decadal ENSO-like variability is the similarity between its spatial expression in sea surface temperature (SST) and structure interannual ENSO variability. This may indicate that merely a long-term average over In contrast, subtle differences (namely meridionally broadened tropical SST signature emphasized midlatitude anomalies for pattern) fundamentally different processes are responsible generating on to interdecadal time scale. The present study...
Abstract A set of ensemble model experiments using the National Center for Atmospheric Research Community Model version 3.0 (CAM3) is run to investigate tropical Pacific response midlatitude atmospheric variability associated with North Oscillation (NPO). Heat flux anomalies NPO are used force a simulations during boreal winter (when most energetic), after which forcing switched off and coupled evolves on its own. Sea surface temperature (SST) wind continue amplify in imposed has been shut...
Sustained ocean observations benefit many users and societal goals but could more. Such information is critical for using resources responsibly sustainably as the becomes increasingly important to society. The contributions of nations cooperating develop Global Ocean Observing System has resulted in a strong base global regional observing networks. However, enhancement existing observation system been constrained by flat funding limited cooperation among present potential users. At same...
Abstract The dynamics of thermodynamically coupled disturbances in the tropics that bear a strong resemblance to observed meridional mode variations are investigated using two simple linear models. Both models involve an ocean equation atmosphere via linearized effect zonal wind on surface bulk latent heat flux. differ their atmospheric components, which consist (i) Gill–Matsuno style model free troposphere heating is parameterized be linearly proportional sea temperature and (ii)...