Seasonal forecasting of subsurface marine heatwaves

Communications Earth & Environment, Journal Year: 2023, Volume and Issue: 4(1)

Published: June 26, 2023

Abstract Marine heatwaves damage marine ecosystems and services, with effects identified mostly below the ocean surface. To create a truly user-relevant detection system, it is necessary to provide subsurface forecasts. Here, we demonstrate feasibility of seasonal forecasting by using upper heat content. We validate surface events forecast an operational dynamical system against satellite observations reanalysis, respectively. show that indicators summer (number days, strongest intensity, number events) are predicted greater skill than equivalents across much global ocean. identify regions which do not display significant but could still benefit from accurate early warning tools (e.g., mid-latitudes). The used here outperforms persistence model widely influenced warming trends, demonstrating ability capture relevant subseasonal variability.

Language: Английский

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A Multi‐Model Ensemble of Baseline and Process‐Based Models Improves the Predictive Skill of Near‐Term Lake Forecasts

Water Resources Research, Journal Year: 2024, Volume and Issue: 60(3)

Published: March 1, 2024

Abstract Water temperature forecasting in lakes and reservoirs is a valuable tool to manage crucial freshwater resources changing more variable climate, but previous efforts have yet identify an optimal modeling approach. Here, we demonstrate the first multi‐model ensemble (MME) reservoir water forecast, method that combines individual model strengths single framework. We developed two MMEs: three‐model process‐based MME five‐model includes empirical models forecast profiles at temperate drinking reservoir. found improved performance by 8%–30% relative MME, as quantified using aggregated probabilistic skill score. This increase was due large improvements bias despite increases uncertainty. High correlation among resulted little improvement models. The utility of MMEs highlighted results: (a) no performed best every depth horizon (days future), (b) avoided poor performances rarely producing worst for any forecasted period (<6% ranked forecasts over time). work presents example how existing can be combined improve discusses value utilizing MMEs, rather than models, operational forecasts.

Language: Английский

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Influence of the 2015–2016 El Niño on the record-breaking mangrove dieback along northern Australia coast

Scientific Reports, Journal Year: 2021, Volume and Issue: 11(1)

Published: Oct. 14, 2021

Abstract This study investigates the underlying climate processes behind largest recorded mangrove dieback event along Gulf of Carpentaria coast in northern Australia late 2015. Using satellite-derived fractional canopy cover (FCC), variation canopies during recent decades are studied, including a severe 2015–2016. The relationship between FCC and conditions is examined with focus on possible role 2015–2016 El Niño altering favorable sustaining mangroves. shown to be coherent low-frequency component sea level height (SLH) related Southern Oscillation (ENSO) cycle equatorial Pacific. SLH drop associated identified crucial factor leading event. A stronger occurred austral autumn winter, when anomalies were about 12% than previous very strong events. persistent dry season year was seasonally at its lowest, so potentially exposed mangroves unprecedented hostile conditions. influence other key factors also discussed, multiple linear regression model developed understand combined important variables variation.

Language: Английский

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The Global Drivers of Chronic Coastal Flood Hazards Under Sea‐Level Rise

Earth s Future, Journal Year: 2023, Volume and Issue: 11(8)

Published: Aug. 1, 2023

Abstract We present the first global estimates of annual average exceedances contemporary minor, moderate, and major flood levels under sea‐level rise (SLR). Applying established methods, we show that minor flooding will occur most days worldwide 0.7 m SLR. Moderate occurs at same frequency 1.0 Local regional differences in threshold elevations, tidal ranges, non‐tidal variability lead to SLR required for this chronic emerge. Lower thresholds, smaller larger extreme skew surges mean can emerge with less discuss several implications these findings coastal hazard assessments. First, tide‐driven water level dominates weather‐driven when determining locations' propensities frequent Second, centimeter‐accurate information is necessary accurately estimate future hazards. Third, locations floods may not be those have develop Rapid Assessment Framework Frequent Flood Transitions (RAFFFTS) apply previously considered studies. RAFFFTS robustly identify potential hotspots using only 1‐year observational records. anticipate a valuable tool identifying risk SLR, complementing existing tools changes episodic floods.

Language: Английский

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Improved capabilities of global ocean reanalyses for analysing sea level variability near the Atlantic and Gulf of Mexico Coastal U.S.

Frontiers in Marine Science, Journal Year: 2024, Volume and Issue: 11

Published: Feb. 22, 2024

Realistic representation of monthly sea level anomalies in coastal regions has been a challenge for global ocean reanalyses. This is especially the case where levels are influenced by western boundary currents such as near U.S. Atlantic Coast and Gulf Mexico. For these regions, most reanalyses compare poorly to observations. Problems include errors data assimilation horizontal resolutions that too coarse simulate energetic like Stream Loop Current System. However, model capabilities advancing with improved higher resolution. Here, we show some current-generation produce skill when compared satellite altimetry observations surface heights. Using tide gauge verification, find highest associated GLORYS12 HYCOM Both systems assimilate have eddy-resolving (1/12°). We found less three other (ACCESS-S2, ORAS5, ORAP6) coarser, though still eddy-permitting, (1/4°). The operational reanalysis from ECMWF (ORAS5) their pilot (ORAP6) provide an interesting comparison because latter assimilates globally more weight, well assimilating over continental shelves. attributes many gauges. also assessed older (CFSR), which lowest likely due its lower resolution (1/2°) lack assimilation. ACCESS-S2 likewise does not altimetry, although much better than CFSR only somewhat ORAS5. Since flooding anomalies, recent development skilful on timescales may be useful understanding physical processes flood risks.

Language: Английский

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A novel statistical approach to predict seasonal high tide flooding

Frontiers in Marine Science, Journal Year: 2022, Volume and Issue: 9

Published: Dec. 8, 2022

Sea level rise is increasing the frequency of high tide flooding in coastal communities across United States. Although occurrence and severity high-tide will continue to increase, skillful prediction on monthly-to-annual time horizons lacking most regions. Here, we present an approach predict daily likelihood at locations throughout U.S. using a novel probabilistic modeling that relies relative sea-level rise, predictions, climatological non-tidal residuals as measured by NOAA gauges. A retrospective skill assessment sea information indicates this 61 out 92 gauges where least 10 flood days occurred from 1997–2019. In case, day occurs when observed water exceeds gauge-specific threshold. For these gauges, average 35% all floods are accurately predicted model, with over half 18 The corresponding False-Alarm-Rate less than 10% for Including mean anomaly persistence leads 1 3 months further improves model many locations, especially Pacific Islands West Coast. Model shown increase substantially nearly tides more frequently exceed Assuming intermediate amount likely be 93 94 projected have regular 2040. These results demonstrate viable incorporated into decision-support products provide guidance days. Further, structure enable future incorporation predictions numerical, statistical, andmachine learning forecast systems.

Language: Английский

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The effect of tidal range and mean sea-level changes on coastal flood hazards at Lakes Entrance, south-east Australia

Journal of Southern Hemisphere Earth System Science, Journal Year: 2023, Volume and Issue: 73(2), P. 116 - 130

Published: May 24, 2023

Despite being well-documented in other countries, the roles that anthropogenically induced changes and natural variability tidal processes play modulating coastal flood frequencies have not been investigated Australia. Here we conduct a brief assessment of around We then apply simple attribution framework to quantify separate joint effects range increasing relative mean sea level on nuisance frequency at location with largest range, Lakes Entrance, Victoria. To understand how these affect hazards, consider threshold based recent impact surveys. Results show increases heights high tides over years exerted large influence frequencies. These are potentially linked channel dredging regimes. 93% days since 2009 would occurred without or coincident level. demonstrate importance considering estuarine hazard assessments for future planning, even if do represent substantial threat today. discuss implications this study work hazards benefits impact-based thresholds such hazards.

Language: Английский

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Skill assessment of seasonal forecasts of ocean variables

Frontiers in Marine Science, Journal Year: 2024, Volume and Issue: 11

Published: May 21, 2024

There is growing demand for seasonal forecast products marine applications. The availability of consistent and sufficiently long observational records ocean variables permits the assessment spatial distribution skill from forecasts. Here we use state-of-the-art temporal sea surface temperature (SST), height (SSH) upper 300m heat content (OHC) to quantify skill, up 2 seasons ahead, two operational forecasting systems contributing multi-model Copernicus Climate Change Services (C3S). This study presents ensemble mean in terms anomaly correlation root square error compares it persistence climatological benchmarks. comparative among sheds light on sources/limits predictability at time scales, as well nature model errors. Beyond these standard verification metrics, also evaluate ability models represent observed long-term trends. Results show that trends contribute Although forecasts capture general, some regional aspects remain challenging. Part errors can be attributed specific initialization, but others, such overestimation warming Eastern Pacific are influenced by error. Skill gains obtained improving trend representation future systems. In meantime, a calibration procedure corrects linear produce substantial gains. results calibrated beat both benchmark almost every location all initial dates lead times. demonstrate value applications highlight importance representing decadal variability level.

Language: Английский

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Skillful multiyear to decadal predictions of sea level in the North Atlantic Ocean and U.S. East Coast

Communications Earth & Environment, Journal Year: 2023, Volume and Issue: 4(1)

Published: Nov. 17, 2023

Abstract Long-term sea-level rise and multiyear to decadal sea level variations pose substantial risks for flooding erosion in coastal communities. Here we use observations climate model predictions show that along the U.S. East Coast are skillfully predictable 3 10 years advance. The most component of is a basin scale upward trend, decade advance primarily response increasing greenhouse gases. Significant additional predictability comes from multidecadal Atlantic Meridional Overturning Circulation (AMOC). While perfect simulations AMOC-related 5-7 years, biases initialization uncertainties reduce realized predictive skill 3-5 depending on location. Overall, gas warming AMOC lead prediction Coast. Such could have significant societal benefit planning adaptation.

Language: Английский

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Statistical Downscaling of Seasonal Forecasts of Sea Level Anomalies for U.S. Coasts

Geophysical Research Letters, Journal Year: 2023, Volume and Issue: 50(4)

Published: Feb. 21, 2023

Abstract Increasing coastal inundation risk in a warming climate will require accurate and reliable seasonal forecasts of sea level anomalies at fine spatial scales. In this study, we explore statistical downscaling monthly hindcasts from six current prediction systems to provide high‐resolution along the North American coast, including several tide gauge stations. This involves applying seasonally invariant operator, constructing by linearly regressing (1/12°) ocean reanalysis data against its coarse‐grained (1°) counterpart, each hindcast ensemble member for period 1982–2011. The resulting have significantly more deterministic skill than original interpolated onto grid. Most improvement occurs during summer fall, without impacting seasonality noted previous studies. Analysis operator reveals that it boosts amplifying most predictable patterns while damping less patterns.

Language: Английский

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