Emanuele Di Lorenzo

• PhD Scripps Institution of Oceanography, UCSD
• Professor at Brown University

Between the winters of 2013/14 and 2014/15 during the strong North American drought, the northeast Pacific experienced the largest marine heatwave ever recorded. Here we combine observations with an ensemble of climate model simulations to show that teleconnections between the North Pacific and the weak 2014/2015 El Niño linked the atmospheric forc...

Long-term time series of marine ecological indicators often are characterized by large-amplitude state transitions that can persist for decades. Understanding the significance of these variations depends critically on the underlying hypotheses characterizing expected natural variability. Using a linear autoregressive model in combination with long-...

Decadal fluctuations of the ocean and atmosphere over the North Pacific Ocean significantly affect the weather and climate of North America and Eurasia. They also cause transitions between different states of marine ecosystems across the Pacific Ocean. An important fraction of North Pacific low-frequency variability is linked to the North Pacific G...

Decadal fluctuations in salinity, nutrients, chlorophyll, a variety of zooplankton taxa, and fish stocks in the Northeast Pacific are often poorly correlated with the most widely-used index of large-scale climate variability in the region - the Pacific Decadal Oscillation (PDO). We define a new pattern of climate change, the North Pacific Gyre Osci...

The El Niño–Southern Oscillation (ENSO) drives large changes in global climate patterns from year to year, yet its sensitivity to continued anthropogenic greenhouse forcing is uncertain. We analyzed fossil coral reconstructions of ENSO spanning the past 7000 years from the Northern Line Islands, located in the center of action for ENSO. The corals...

Marine heatwaves and ocean acidification extreme events are periods during which temperature and acidification reach statistically extreme levels (90th percentile), relative to normal variability, potentially endangering ecosystems. As the threats from marine heatwaves and ocean acidification extreme events grow with climate change, there is need f...

Plain Language Summary Observations have consistently highlighted prominent decadal climate variability in the Niño4 region, yet the underlying cause of this distinct pattern remains largely elusive. In this study, we use composite analysis during the phase transition of Tropical Pacific Decadal Variability (TPDV) and modeling experiments to elucid...

Plain Language Summary The tropical Pacific climate variability exerts a strong impact on global climate, regional weather, and marine ecosystems. The tropical and extratropical Pacific are closely coupled with each other through oceanic and atmospheric processes. Previous studies have shown that the southern and northern extratropical Pacific (SEP...

Climate-driven changes in marine ecosystem structure and function adversely impact the biodiversity and sustainability of living marine resources, food security, and the resilience of coastal communities. Understanding how climate change impacts marine ecosystem biodiversity and global fisheries, i.e. the “climate-biodiversity-fisheries nexus”, is...

Despite tremendous progress in algorithm development, computational efficiency and transition into operations over the past two decades, coastal modeling still lacks scientific rigor due to proliferation of many ‘gray’ areas related to various modeling choices made by modelers. In this paper, we propose some guiding principles for the modeling comm...

We demonstrate the key role of off-equatorial subsurface temperature anomalies in driving the phase transition of Tropical Pacific Decadal Variability (TPDV) using observation and model experiments. During the positive phase of TPDV, anomalous atmospheric responses in the off-equatorial northwestern Pacific induce positive Ekman pumping. The result...

Marine heatwaves (MHW) and ocean acidification extreme events (OAX) are periods during which temperature and acidification reach extreme levels, endangering ecosystems. As the threats from MHW and OAX grow with climate change, there is need for skillful predictions of events months-to-years in advance. Previous work has demonstrated that climate mo...

Post Hurricane Abnormal Water Level (PHAWL) poses a persistent inundation threat to coastal communities, yet unresolved knowledge gaps exist regarding its spatiotemporal impacts and causal mechanisms. Using a high-resolution coastal model with a set of observations, we find that the PHAWLs are up to 50 cm higher than the normal water levels for sev...

Anthropogenic carbon emissions and associated climate change are driving rapid warming, acidification, and deoxygenation in the ocean, which increasingly stress marine ecosystems. On top of long‐term trends, short term variability of marine stressors can have major implications for marine ecosystems and their management. As such, there is a growing...

Plain Language Summary Tropical Pacific Decadal‐scale Variability (TPDV) has been shown to impact global‐scale climate fluctuations, weather regimes, and temperature trends such as the 1998–2012 global warming hiatus. Understanding and predicting TPDV's impacts strongly rely on climate model simulations and projections. However, the models show key...

Assessing uncertainty in future climate projections requires understanding both internal climate variability and external forcing. For this reason, single‐model initial condition large ensembles (SMILEs) run with Earth System Models (ESMs) have recently become popular. Here we present a new 20‐member SMILE with the Energy Exascale Earth System Mode...

Anthropogenic carbon emissions and associated climate change are driving rapid warming, acidification, and deoxygenation in the ocean, which increasingly stress marine ecosystems. On top of long-term trends, short term variability of marine stressors can have major implications for marine ecosystems and their management. As such, there is a growing...

Marine heatwaves (MHWs)—extremely warm, persistent sea surface temperature (SST) anomalies causing substantial ecological and economic consequences—have increased worldwide in recent decades. Concurrent increases in global temperatures suggest that climate change impacted MHW occurrences, beyond random changes arising from natural internal variabil...

Previous studies have documented a strong relationship between marine ecosystems and large-scale modes of sea surface height (SSH) and sea surface temperature (SST) variability in the North Pacific such as the Pacific Decadal Oscillation and the North Pacific Gyre Oscillation. In the central and western North Pacific along the Kuroshio-Oyashio Exte...

Multi-year El Niño events induce severe and persistent floods and droughts worldwide, with significant socioeconomic impacts, but the causes of their long-lasting behaviors are still not fully understood. Here we present a two-way feedback mechanism between the tropics and extratropics to argue that extratropical atmospheric variability associated...

The dynamics controlling the spatial and temporal expressions of storm surges over the coastal wetlands and communities of the South Atlantic Bight (SAB) is complex and not well understood. Leveraging a newly developed high-density hyper-local network of water level sensors in the North Georgia coast, we implement and test an unstructured numerical...

Marine fish populations commonly exhibit low-frequency fluctuations in biomass that can cause catch volatility and thus endanger the food and economic security of dependent coastal societies. Such variability has been linked to fishing intensity, demographic processes and environmental variability, but our understanding of the underlying drivers re...

Plain Language Summary It is widely accepted that Tropical modes of variability, such as El Niño–Southern Oscillation (ENSO) and the IOD, play a crucial role in modulating the year‐to‐year variability in Australian precipitation and extreme weather events, including conditions favorable to record‐breaking bushfire events such as the catastrophic 20...

A majority of El Niño/Southern Oscillation (ENSO) events are preceded by the North Pacific Meridional Mode (NPMM), a dominant coupled ocean–atmospheric mode of variability. How the precursory NPMM forcing on ENSO responds to greenhouse warming remains unknown. Here, using climate model ensembles under high-emissions warming scenarios, we find an en...

A decades-long affair Decadal climate variability and change affects nearly every aspect of our world, including weather, agriculture, ecosystems, and the economy. Predicting its expression is thus of critical importance on multiple fronts. Power et al . review what is known about tropical Pacific decadal climate variability and change, the degree...

Teleconnections from the Tropics energize variations of the North Pacific climate, but detailed diagnosis of this relationship has proven difficult. Simple univariate methods, such as regression on El Niño-Southern Oscillation (ENSO) indices, may be inadequate since the key dynamical processes involved -- including ENSO diversity in the Tropics, re...

Efforts to manage living marine resources (LMRs) under climate change need projections of future ocean conditions, yet most global climate models (GCMs) poorly represent critical coastal habitats. GCM utility for LMR applications will increase with higher spatial resolution but obstacles including computational and data storage costs, obstinate reg...

The climate variability of the Kuroshio-Oyashio Extension (KOE) and North Pacific Transition Zone (NPTZ) exerts a strong control on marine populations that are sensitive to the strong productivity gradients between the subtropical and subpolar recirculation gyres. In observations, the relationship between KOE, NPTZ and productivity is evident in th...

Quasi-decadal climate of the Kuroshio Extension (KE) is pivotal to understanding the North Pacific coupled ocean-atmosphere dynamics and their predictability. Recent observational studies suggest that extratropical-tropical coupling between the KE and the central tropical Pacific El Niño Southern Oscillation (CP-ENSO) leads to the observed preferre...

The inner shelf, the transition zone between the surf zone and the mid shelf, is a dynamically complex region with the evolution of circulation and stratification driven by multiple physical processes. Cross-shelf exchange through the inner shelf has important implications for coastal water quality, ecological connectivity, and lateral movement of...

Some questions remain concerning the record‐breaking 2013–2015 Northeast Pacific marine heatwave (MHW) event: was it exceptional or merely the most pronounced of a group of similar events, and was its intensity and multiyear duration driven by internal extratropical processes or did the tropics play an important role? By analyzing the statistical b...

Quasi-decadal climate of the Kuroshio Extension (KE) is pivotal to understanding the North Pacific coupled ocean-atmosphere dynamics and their predictability. Recent observational studies suggest that extratropical-tropical coupling between the KE and the central tropical Pacific El Niño Southern Oscillation (CP-ENSO) leads to the observed preferre...

Observational analyses suggest that a significant fraction of the Tropical Pacific Decadal Variability (TPDV) (∼60%-70%) is energized by the combined action of extra-tropical precursors of the El Niño Southern Oscillation (ENSO) originating from the North and South Pacific. Specifically, the growth and decay of the basin-scale TPDV pattern (∼timesc...

In order to understand how North Pacific (NP) marine ecosystems have varied, 120 marine biological time series for both the western (29 time series) and eastern (91 time series) NP were analyzed with a Principal Component Analysis (PCA) for the period 1965–2006. This is the first attempt to conduct a multivariate analysis for a large number of mari...

The El Niño-Southern Oscillation (ENSO) represents the largest source of year-to-year global climate variability. While earth system models suggest a range of possible shifts in ENSO properties under continued greenhouse gas forcing, many centuries of preindustrial climate data are required to detect a potential shift in the properties of recent EN...

Off-equatorial wind anomalies on seasonal timescales from both the North and South Pacific, known as “precursors” of the El Niño Southern Oscillation (ENSO), have been shown to independently trigger the ENSO feedbacks in the tropics and its teleconnections to the extra-tropics. However, the impacts of ENSO precursors on Tropical Pacific Decadal-sca...

Marine ecosystem forecasting is an area of active research and rapid development. Promise has been shown for skillful prediction of physical, biogeochemical, and ecological variables on a range of timescales, suggesting potential for forecasts to aid in the management of living marine resources and coastal communities. However, the mechanisms under...

Climate variability and climate change in Eastern Boundary Upwelling Systems (EBUS) affect global marine ecosystems services. We use passive tracers in a global ocean model hindcast at eddy-permitting resolution to diagnose EBUS low-frequency variability over 1958–2015 period. The results highlight the uniqueness of each EBUS in terms of drivers an...

Many coastal areas host rich marine ecosystems and are also centers of economic activities, including fishing, shipping and recreation. Due to the socioeconomic and ecological importance of these areas, predicting relevant indicators of the ecosystem state on sub-seasonal to interannual timescales is gaining increasing attention. Depending on the a...

The Kuroshio Extension (KE) exhibits prominent decadal fluctuations that enhance the low-frequency variability of North Pacific climate. Using available observations, we show evidence that a preferred decadal timescale in the KE emerges from the interaction between KE and the central tropical Pacific via Meridional Modes. Specifically, we show that...

The causes of the extreme and persistent warming in the Northeast Pacific from the winter of 2013/14 to that of 2014/15 are still not fully understood. While global warming may have contributed, natural influences may also have played a role. El Niño events are often implicated in anomalously warm conditions along the US West Coast (USWC). However,...

A series of five realistic, nested, hydrostatic numerical ocean model simulations are used to study semidiurnal internal tide generation and propagation from the continental slope, through the shelf break and to the midshelf adjacent to Point Sal, CA. The statistics of modeled temperature and horizontal velocity fluctuations are compared to midshel...

“Forecasting and Understanding Trends, Uncertainty and Responses of North Pacific Marine Ecosystems” (FUTURE) is the flagship integrative Scientific Program undertaken by the member nations and affiliates of the North Pacific Marine Science Organization (PICES). A principal goal of FUTURE is to develop a framework for investigating interactions acr...

Plain Language Summary El Niño–Southern Oscillation (ENSO) and the Tropical Pacific decadal variability (TPDV) exert a strong influence over the climate of large parts of the world. To understand and predict tropical Pacific variability, it is necessary to study all those oceanic and atmospheric processes that act as triggers and energizers of ENSO...

Purpose of Review This paper reviews recent progress in the understanding and prediction of pacific decadal variability (PDV). The PDV is now recognized to consist of multiple ocean-atmosphere modes and to be caused by multiple processes. At the leading order, PDV can be viewed as the reddening process of stochastic atmospheric variability on the e...

Population oscillations in multi-species or even single species systems are well-known but have rarely been detected at the lower trophic levels in marine systems. Nitrogen fixing cyanobacteria are a major component of the Baltic Sea ecosystem and sometimes form huge surface accumulations covering most of the sea surface. By analysing a satellite-d...

Nitrogen fixing cyanobacteria are a major component of the Baltic Sea ecosystem and sometimes form huge surface accumulations covering most of the sea surface. By analysing a satellite-derived 39-year (1979-2017) data archive of surface cyanobacteria concentrations we have found evidence of strikingly regular interannual oscillations in cyanobacter...

More details on Methods and Materials

Along the western margin of North America, the winter expression of the North Pacific High (NPH) strongly influences interannual variability in coastal upwelling, storm track position, precipitation, and river discharge. Coherence among these factors induces covariance among physical and biological processes across adjacent marine and terrestrial e...

Pacific decadal variability has strong impacts on the statistics of weather, atmosphere extremes, droughts, hurricanes, marine heatwaves and marine ecosystems. Sea surface temperature (SST) observations show that the variance of the El Niño-like decadal variability has increased by ~30% (1920-2015) with a stronger coupling between the major Pacific...

The marine heatwave of 2014/2015 in the Northeast Pacific caused significant impacts on marine ecosystems and fisheries. While several studies suggest that land and marine heatwaves may intensify under climate change, less is known about the prolonged multiyear nature (~2 years) of the Northeast Pacific events. Examination of reanalysis products an...

The oxygen of the source waters that feed the upwelling in the California Current System show prominent multi-decadal fluctuations that are not significantly correlated with the dominant modes of Pacific climate variability. By combining observations and ocean reanalysis products between 1950-2010, we show that decadal changes in oxygen are linked...

Juvenile jack mackerel were found in 2009 in the Challenger break and the East Pacific ridge (CHAEPR). This seamount region is ~3500 km from the coastal historic jack mackerel nursery grounds off Chile (north of 30°S). We reviewed historic evidence of juveniles around this seamount and data on several local environmental conditions: sea surface tem...

In recent years, persistent quasi-zonal jets or striations have been ubiquitously detected in the world ocean using satellite and in situ data as well as numerical models. This study aims at determining the role of mesoscale eddies in the generation and persistence of striations off Chile in the eastern South Pacific. A 50-year climatological integ...

Changes in surface heat fluxes affect several climate processes controlling the Mediterranean climate. These include the winter formation of deep waters, which is the primary driver of the Mediterranean Sea overturning circulation. Previous studies that characterize the spatial and temporal variability of surface heat flux anomalies over the basin...

Events of recent years—including extended droughts across California, record fires across western Canada, and destabilization of marine ecosystems—highlight the profound impact of multi-annual to decadal-scale climate shifts upon physical, biological and socio-economic systems. While previous research has focused on the influence of decadal-scale c...

The seasonal and interannual variability of vertical transport (upwelling/downwelling) has been relatively well studied, mainly for the California Current System, including low-frequency changes and latitudinal heterogeneity. The aim of this work was to identify potentially predictable patterns in upwelling/downwelling activity along the North Amer...

The Pacific decadal oscillation (PDO), the dominant year-round pattern of monthly North Pacific sea surface temperature (SST) variability, is an important target of ongoing research within the meteorological and climate dynamics communities, and is central to the work of many geologists, ecologists, natural resource managers, and social scientists....

Sustained droughts over the Northwestern US can alter water availability to the region's agricultural, hydroelectric, and ecosystem service sectors. Here we analyze decadal variations in precipitation across this region and reveal their relation to the slow (~10 year) progression of an atmospheric pressure pattern around the North Pacific, which we...

Pacific low-frequency variability (timescale > 8 year) exhibits a well-known El Niño-like pattern of basin-scale sea surface temperature, which is found in all the major modes of Pacific decadal climate. Using a set of climate model experiments and observations, we decompose the mechanisms contributing to the growth, peak and decay of the Pacific l...

Significance Historically, many Pacific salmon species were thought to be influenced by the Pacific Decadal Oscillation (PDO), an indicator of ocean conditions, associated with El Niños. As the nature of El Niños has changed recently, another ocean indicator, the North Pacific Gyre Oscillation (NPGO) has become more important. By comparing time ser...

El Niño Southern Oscillation (ENSO) is a naturally occurring mode of tropical Pacific variability, with global impacts on society and natural ecosystems. While it has long been known that El Niño events display a diverse range of amplitudes, triggers, spatial patterns, and life cycles, the realization that ENSO's impacts can be highly sensitive to...

The Southeast Pacific, which encompasses the coasts of Peru and Chile, is one of the world's most productive regions resulting principally from the upwelling of subsurface nutrient-rich waters. Over the satellite altimetry era, there have been numerous evidence that surface mesoscale eddies play an important role in the offshore transport of rich c...

An ensemble of climate models predicts that winds along the world's coasts will intensify because of global warming, inducing more ocean upwelling - a process that will affect the health of coastal marine ecosystems. See Letter p.390

Decadal changes in sea surface temperature (SST) in the Gulf of Alaska are linked to long-term transitions in the marine ecosystem. While previous studies have identified the atmospheric variability of the Aleutian Low as an important driver of Ekman pumping and low-frequency SST anomalies, the role of subsurface gyre-scale dynamics remains unexplo...

International scientists from seven countries with expertise in decadal climate variability met to review and critically assess recent progress in, and new directions for, understanding decadal climate variability and cross-scale interactions.

Historical hydrographic data (1984–2012) from the California Cooperative Oceanic Fisheries Investigations (CalCOFI) program and global reanalysis products were used to quantify recent water mass variability off the coast of southern California. Dissolved oxygen concentrations continued to decline within the lower pycnocline, concurrent with strong...

The impacts of the El Niño Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO) on the ecology of the northeast Pacific are well known. However, recently there has been a shift in the dominance of El Niño events from the eastern Pacific (canonical) El Niño, to the central Pacific (Modoki) El Niño, concurrent with a strengthening of...

Recent observations suggest that the mean mesoscale oceanic zonal velocity field is dominated by alternating jet-like features often referred to as striations. Here the generating dynamics of Northeast Pacific striations are explored with a set of 120-year eddy-permitting model simulations. Simulations are conducted with decreasing complexity towar...

Thee goal of the Pacific Ocean Boundary Ecosystem Climate Study (POBEX) was to diagnose the large-scale climate controls on regional transport dynamics and lower-trophic marine ecosystem variability in Pacific Ocean boundary systems. An international team of collaborators shared observational and eddy-resolving modeling datasets in the Northeast Pa...

A primary focus of the US Global Ocean Ecosystem Dynamics (GLOBEC) program was to identify the mechanisms of ecosystem response to largescale climate forcing under the assumption that bottom-up forcing controls a large fraction of marine ecosystem variability. At the beginning of GLOBEC, the prevailing bottom-up forcing hypothesis was that climate-...

The goal of the Pacific Ocean Boundary Ecosystem and Climate Study (POBEX) was to diagnose the large-scale climate controls on regional transport dynamics and lower trophic marine ecosystem variability in Pacific Ocean boundary systems. An international team of collaborators shared observational and eddyresolving modeling data sets collected in the...

This study addresses the occurrence, severity, and extent of hypoxia over the continental shelf of the northern California Current (40-48.5°N latitude) from 1998 to 2012. Clear seasonal trends exist in the timing and duration of hypoxia. The highest bottom-water dissolved oxygen concentrations occurred from November to March, and levels below the 1...

Two numerical ocean models are used to study the baroclinic response to forcing by localized wind stress curl (i.e., a wind-forced beta plume, which is a circulation cell developing to the west of the source region and composed of a set of zonal jets) with implications for the Hawaiian Lee Countercurrent (HLCC): an idealized primitive equation mode...