The effect of global climate change on the future distribution of economically important macroalgae (seaweeds) in the northwest Atlantic

An increase in greenhouse gas emissions has led to a rise in average global air and ocean temperatures. Increased sea surface temperatures can cause changes in species’ distributions, particularly those species close to their thermal tolerance limits. We use a bioclimate envelope approach to assess potential shifts in the range of marine macroalgae harvested in North American waters: rockweed ( Fucus vesiculosus Linnaeus, 1753), serrated wrack ( Fucus serratus Linnaeus, 1753), knotted wrack ( Ascophyllum nodosum (Linnaeus) Le Jolis, 1863), carrageen moss ( Chondrus crispus Stackhouse, 1797), and three kelp species ( Laminaria digitata (Hudson) J.V. Lamouroux, 1813; Saccharina latissima (Linnaeus) C.E. Lane, C. Mayes, Druehl et G.W. Saunders, 2006; and Saccharina longicruris (Bachelot de la Pylaie) Kuntze, 1891). We determined species’ thermal limits from the current sea surface temperatures associated with their geographical distributions. Future distributions were based on sea surface temperatures projected for the year ∼2100 by four atmosphere-ocean general circulation models and earth system models for regional concentration pathways (RCPs) 4.5 and 8.5. Future distributions based on RCP 8.5 indicate that the presence of all but rockweed ( F. vesiculosus) is likely to be threatened by warming waters in the Gulf of St. Lawrence and along the Atlantic coast of Nova Scotia. Range retractions of macroalgae will have significant ecological and economic effects including impacts on commercial fisheries and harvest rates and losses of floral and faunal biodiversity and production, and should be considered in the designation of marine protected areas.

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Do climate simulations from models forced by averaged sea surface temperatures represent actual dynamics?

Nonlinear Processes in Geophysics ◽

10.5194/npg-4-93-1997 ◽

1997 ◽

Vol 4 (2) ◽

pp. 93-100 ◽

Cited By ~ 4

Author(s):

P. J. Roebber ◽

A. A. Tsonis ◽

J. B. Elsner

Keyword(s):

General Circulation ◽

Climatic Variability ◽

General Circulation Models ◽

Ocean Model ◽

Coupled Systems ◽

Sea Surface ◽

Sea Surface Temperatures ◽

Surface Temperatures ◽

Fully Coupled ◽

Low Order

Abstract. Recently atmospheric general circulation models (AGCMs) forced by observed sea surface temperatures (SSTs) have offered the possibility of studying climate variability over periods ranging from years to decades. Such models represent and alternative to fully coupled asynchronous atmosphere ocean models whose long term integration remains problematic. Here, the degree of the approximation represented by this approach is investigated from a conceptual point of view by comparing the dynamical properties of a low order coupled atmosphere-ocean model to those of the atmospheric component of the same model when forced with monthly values of SST derived from the fully coupled simulation. The low order modelling approach is undertaken with the expectation that it may reveal general principles concerning the dynamical behaviour of the forced versus coupled systems; it is not expected that such an approach will determine the details of these differences, for which higher order modelling studies will be required. We discover that even though attractor (global) averages may be similar, local dynamics and the resultant variability and predictability characteristics differ substantially. These results suggest that conclusions concerning regional climatic variability (in time as well as space) drawn from forced modelling approaches may be contaminated by an inherently unquantifiable error. It is therefore recommended that this possibility be carefully investigated using state-of-the-art coupled AGCMs.

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Relationships among Intermodel Spread and Biases in Tropical Atlantic Sea Surface Temperatures

Journal of Climate ◽

10.1175/jcli-d-18-0846.1 ◽

2019 ◽

Vol 32 (12) ◽

pp. 3615-3635 ◽

Cited By ~ 2

Author(s):

Elsa Mohino ◽

Belén Rodríguez-Fonseca ◽

C. Roberto Mechoso ◽

Teresa Losada ◽

Irene Polo

Keyword(s):

General Circulation ◽

General Circulation Models ◽

Meridional Overturning Circulation ◽

Sea Surface ◽

Cmip5 Models ◽

Sea Surface Temperatures ◽

Tropical Atlantic ◽

Surface Temperatures ◽

Second Mode ◽

The Mean

Abstract State-of-the-art general circulation models show important systematic errors in their simulation of sea surface temperatures (SST), especially in the tropical Atlantic. In this work the spread in the simulation of climatological SST in the tropical Atlantic by 24 CMIP5 models is examined, and its relationship with the mean systematic biases in the region is explored. The modes of intermodel variability are estimated by applying principal component (PC) analysis to the SSTs in the region 70°W–20°E, 20°S–20°N. The intermodel variability is approximately explained by the first three modes. The first mode is related to warmer SSTs in the basin, shows worldwide connections with same-signed loads over most of the tropics, and is connected with lower low cloud cover over the eastern parts of the subtropical oceans. The second mode is restricted to the Atlantic, where it shows negative and positive loads to the north and south of the equator, respectively, and is connected to a too weak Atlantic meridional overturning circulation (AMOC). The third mode is related to the double intertropical convergence zone bias in the Pacific and to an interhemispheric asymmetry in the net radiation at the top of the atmosphere. The structure of the second mode is closer to the mean bias than that of the others in the tropical Atlantic, suggesting that model difficulties with the AMOC contribute to the regional biases.

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A spatiotemporal reconstruction of sea-surface temperatures in the North Atlantic during Dansgaard–Oeschger events 5–8

Climate of the Past ◽

10.5194/cp-14-901-2018 ◽

2018 ◽

Vol 14 (6) ◽

pp. 901-922 ◽

Cited By ~ 6

Author(s):

Mari F. Jensen ◽

Aleksi Nummelin ◽

Søren B. Nielsen ◽

Henrik Sadatzki ◽

Evangeline Sessford ◽

...

Keyword(s):

Surface Temperature ◽

Sea Surface Temperature ◽

North Atlantic ◽

General Circulation ◽

Sea Surface ◽

Reconstruction Method ◽

Sea Surface Temperatures ◽

Proxy Data ◽

Surface Temperatures ◽

Temperature Reconstructions

Abstract. Here, we establish a spatiotemporal evolution of the sea-surface temperatures in the North Atlantic over Dansgaard–Oeschger (DO) events 5–8 (approximately 30–40 kyr) using the proxy surrogate reconstruction method. Proxy data suggest a large variability in North Atlantic sea-surface temperatures during the DO events of the last glacial period. However, proxy data availability is limited and cannot provide a full spatial picture of the oceanic changes. Therefore, we combine fully coupled, general circulation model simulations with planktic foraminifera based sea-surface temperature reconstructions to obtain a broader spatial picture of the ocean state during DO events 5–8. The resulting spatial sea-surface temperature patterns agree over a number of different general circulation models and simulations. We find that sea-surface temperature variability over the DO events is characterized by colder conditions in the subpolar North Atlantic during stadials than during interstadials, and the variability is linked to changes in the Atlantic Meridional Overturning circulation and in the sea-ice cover. Forced simulations are needed to capture the strength of the temperature variability and to reconstruct the variability in other climatic records not directly linked to the sea-surface temperature reconstructions. This is the first time the proxy surrogate reconstruction method has been applied to oceanic variability during MIS3. Our results remain robust, even when age uncertainties of proxy data, the number of available temperature reconstructions, and different climate models are considered. However, we also highlight shortcomings of the methodology that should be addressed in future implementations.

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An ensemble of AMIP simulations with prescribed land surface temperatures

10.5194/gmd-2018-77 ◽

2018 ◽

Author(s):

Duncan Ackerley ◽

Robin Chadwick ◽

Dietmar Dommenget ◽

Paola Petrelli

Keyword(s):

Surface Temperature ◽

Land Surface ◽

General Circulation ◽

Global Climate ◽

General Circulation Models ◽

Solar Constant ◽

Surface Temperatures ◽

Co2 Concentrations ◽

Land Surface Temperatures ◽

Intercomparison Project

Abstract. General circulation models (GCMs) are routinely run under Atmospheric Modelling Intercomparison Project (AMIP) conditions with prescribed sea surface temperatures (SSTs) and sea ice concentrations (SICs) from observations. These AMIP simulations are often used to evaluate the role of the land and/or atmosphere in causing the development of systematic errors in such GCMs. Extensions to the original AMIP experiment have also been developed to evaluate the response of the global climate to increased SSTs (prescribed) and carbon-dioxide (CO2) as part of the Cloud Feedback Model Intercomparison Project (CFMIP). None of these international modelling initiatives has undertaken a set of experiments where the land conditions are also prescribed, which is the focus of the work presented in this paper. Experiments are performed initially with freely varying land conditions (surface temperature and, soil temperature and mositure) under five different configurations (AMIP, AMIP with uniform 4 K added to SSTs, AMIP SST with quadrupled CO2, AMIP SST and quadrupled CO2 without the plant stomata response, and increasing the solar constant by 3.3 %). Then, the land surface temperatures from the free-land experiments are used to perform a set of “AMIP-prescribed land” (PL) simulations, which are evaluated against their free-land counterparts. The PL simulations agree well with the free-land experiments, which indicates that the land surface is prescribed in a way that is consistent with the original free-land configuration. Further experiments are also performed with different combinations of SSTs, CO2 concentrations, solar constant and land conditions. For example, SST and land conditions are used from the AMIP simulation with quadrupled CO2 in order to simulate the atmospheric response to increased CO2 concentrations without the surface temperature changing. The results of all these experiments have been made publicly available for further analysis. The main aims of this paper are to provide a description of the method used and an initial validation of these AMIP-prescribed land experiments.

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The Transient Circulation Response to Radiative Forcings and Sea Surface Warming*

Journal of Climate ◽

10.1175/jcli-d-14-00035.1 ◽

2014 ◽

Vol 27 (24) ◽

pp. 9323-9336 ◽

Cited By ~ 9

Author(s):

Paul W. Staten ◽

Thomas Reichler ◽

Jian Lu

Keyword(s):

General Circulation ◽

Climate Model ◽

Stratospheric Ozone ◽

Sea Surface ◽

Sea Surface Temperatures ◽

Indirect Response ◽

Radiative Forcings ◽

Surface Warming ◽

Impact Surface ◽

Surface Temperatures

Abstract Tropospheric circulation shifts have strong potential to impact surface climate. However, the magnitude of these shifts in a changing climate and the attending regional hydrological changes are difficult to project. Part of this difficulty arises from the lack of understanding of the physical mechanisms behind the circulation shifts themselves. To better delineate circulation shifts and their respective causes the circulation response is decomposed into 1) the “direct” response to radiative forcings themselves and 2) the “indirect” response to changing sea surface temperatures. Using ensembles of 90-day climate model simulations with immediate switch-on forcings, including perturbed greenhouse gas concentrations, stratospheric ozone concentrations, and sea surface temperatures, this paper documents the direct and indirect transient responses of the zonal-mean general circulation, and investigates the roles of previously proposed mechanisms in shifting the midlatitude jet. It is found that both the direct and indirect wind responses often begin in the lower stratosphere. Changes in midlatitude eddies are ubiquitous and synchronous with the midlatitude zonal wind response. Shifts in the critical latitude of wave absorption on either flank of the jet are not indicted as primary factors for the poleward-shifting jet, although some evidence for increasing equatorward wave reflection over the Southern Hemisphere in response to sea surface warming is seen. Mechanisms for the Northern Hemisphere jet shift are less clear.

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An ensemble of AMIP simulations with prescribed land surface temperatures

Geoscientific Model Development ◽

10.5194/gmd-11-3865-2018 ◽

2018 ◽

Vol 11 (9) ◽

pp. 3865-3881 ◽

Cited By ~ 4

Author(s):

Duncan Ackerley ◽

Robin Chadwick ◽

Dietmar Dommenget ◽

Paola Petrelli

Keyword(s):

Surface Temperature ◽

Land Surface ◽

General Circulation ◽

Global Climate ◽

General Circulation Models ◽

Solar Constant ◽

Surface Temperatures ◽

Co2 Concentrations ◽

Land Surface Temperatures ◽

Intercomparison Project

Abstract. General circulation models (GCMs) are routinely run under Atmospheric Modelling Intercomparison Project (AMIP) conditions with prescribed sea surface temperatures (SSTs) and sea ice concentrations (SICs) from observations. These AMIP simulations are often used to evaluate the role of the land and/or atmosphere in causing the development of systematic errors in such GCMs. Extensions to the original AMIP experiment have also been developed to evaluate the response of the global climate to increased SSTs (prescribed) and carbon dioxide (CO2) as part of the Cloud Feedback Model Intercomparison Project (CFMIP). None of these international modelling initiatives has undertaken a set of experiments where the land conditions are also prescribed, which is the focus of the work presented in this paper. Experiments are performed initially with freely varying land conditions (surface temperature, and soil temperature and moisture) under five different configurations (AMIP, AMIP with uniform 4 K added to SSTs, AMIP SST with quadrupled CO2, AMIP SST and quadrupled CO2 without the plant stomata response, and increasing the solar constant by 3.3 %). Then, the land surface temperatures from the free land experiments are used to perform a set of “AMIP prescribed land” (PL) simulations, which are evaluated against their free land counterparts. The PL simulations agree well with the free land experiments, which indicates that the land surface is prescribed in a way that is consistent with the original free land configuration. Further experiments are also performed with different combinations of SSTs, CO2 concentrations, solar constant and land conditions. For example, SST and land conditions are used from the AMIP simulation with quadrupled CO2 in order to simulate the atmospheric response to increased CO2 concentrations without the surface temperature changing. The results of all these experiments have been made publicly available for further analysis. The main aims of this paper are to provide a description of the method used and an initial validation of these AMIP prescribed land experiments.

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CONTINUUM CLIMATE VARIABILITY: LONG-TERM MEMORY, SCALING, AND 1/F-NOISE

International Journal of Modern Physics B ◽

10.1142/s0217979209063729 ◽

2009 ◽

Vol 23 (28n29) ◽

pp. 5403-5416 ◽

Cited By ~ 41

Author(s):

KLAUS FRAEDRICH ◽

RICHARD BLENDER ◽

XIUHUA ZHU

Keyword(s):

General Circulation ◽

General Circulation Models ◽

Sea Surface ◽

Long Term Memory ◽

Sea Surface Temperatures ◽

Term Memory ◽

Ocean General Circulation Models ◽

Ocean General Circulation ◽

One Year

Continuum temperature variability represents the response of the Earth's climate to deterministic external forcing. Scaling regimes are observed which range from hours to millennia with low frequency fluctuations characterizing long-term memory. The presence of 1/f power spectra in weather and climate is noteworthy: (i) In the tropical atmosphere 1/f scaling ranging from hours to weeks is found for several variables; it emerges as superposition of uncorrelated pulses with individual 1/f spectra. (ii) The daily discharge of the Yangtze shows 1/f within one week to one year, although the precipitation spectrum is white. (iii) Beyond one year mid-latitude sea surface temperatures reveal 1/f scaling in large parts of the global ocean. The spectra can be simulated by complex atmosphere-ocean general circulation models and understood as a two layer heat diffusion process forced by an uncorrelated stochastic atmospheric. Long-term memory on time scales up to millennia are the global sea surface temperatures and the Greenland ice core records (GISP2, GRIP) with δ18 O temperature proxy data during the Holocene. Complex atmosphere ocean general circulation models reproduce this behavior quantitatively up to millennia without solar variability, interacting land-ice and vegetation components.

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Potential effects of climate change on marine growth and survival of Fraser River sockeye salmon

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f95-854 ◽

1995 ◽

Vol 52 (12) ◽

pp. 2651-2659 ◽

Cited By ~ 44

Author(s):

Scott G. Hinch ◽

Michael C. Healey ◽

Ron E. Diewert ◽

Michael A. Henderson ◽

Keith A. Thomson ◽

...

Keyword(s):

General Circulation Model ◽

General Circulation ◽

Sockeye Salmon ◽

Circulation Model ◽

Zooplankton Biomass ◽

Air Pressure ◽

Sea Surface ◽

Fraser River ◽

Sea Surface Temperatures ◽

Surface Temperatures

Simulation results from the Canadian Climate Centre's atmospheric general circulation model (CCC GCM) coupled to a simplified mixed-layer ocean model predict that doubled atmospheric CO2 concentrations would increase northeast Pacific Ocean sea surface temperatures and weaken existing north–south air pressure gradients. On the basis of predicted changes to air pressure and an empirical relationship between wind-driven upwelling and zooplankton biomass, we calculate that production of food for sockeye salmon (Oncorhynchus nerka) may decrease by 5–9%. We developed empirical relationships between sea surface temperature, zooplankton biomass, adult recruitment, and terminal ocean weight for the early Stuart stock of Fraser River sockeye salmon. Our analyses show that warmer sea surface temperatures, larger adult recruitment, and lower zooplankton biomass are correlated with smaller adult sockeye. Bioenergetics modeling suggests that higher metabolic costs in warmer water coupled with lower food availability could cause the observed reductions in size. Warmer sea surface temperatures during coastal migration by juveniles were correlated with lower recruitment 2 yr later. Warmer sea surface temperatures may be a surrogate for increased levels of predation or decreased food during the juvenile stage. We speculate that Fraser sockeye will be less abundant and smaller if the climate changes as suggested by the Canadian Climate Centre's general circulation model.

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The Intraseasonal Variability of the Indian Summer Monsoon Using TMI Sea Surface Temperatures and ECMWF Reanalysis

Journal of Climate ◽

10.1175/2007jcli1850.1 ◽

2008 ◽

Vol 21 (11) ◽

pp. 2519-2539 ◽

Cited By ~ 26

Author(s):

Nicholas P. Klingaman ◽

Hilary Weller ◽

Julia M. Slingo ◽

Peter M. Inness

Keyword(s):

Life Cycle ◽

Indian Ocean ◽

General Circulation ◽

Function Analysis ◽

Intraseasonal Variability ◽

Equatorial Indian Ocean ◽

Sea Surface ◽

Sea Surface Temperatures ◽

Surface Temperatures ◽

Sst Anomalies

Abstract The northward-propagating intraseasonal (30–40 day) oscillation (NPISO) between active and break monsoon phases exerts a critical control on summer-season rainfall totals over India. Advances in diagnosing these events and comprehending the physical mechanisms behind them may hold the potential for improving their predictability. While previous studies have attempted to extract active and break events from reanalysis data to elucidate a composite life cycle, those studies have relied on first isolating the intraseasonal variability in the record (e.g., through bandpass filtering, removing harmonics, or empirical orthogonal function analysis). Additionally, the underlying physical processes that previous studies have proposed have varied, both among themselves and with studies using general circulation models. A simple index is defined for diagnosing NPISO events in observations and reanalysis, based on lag correlations between outgoing longwave radiation (OLR) over India and over the equatorial Indian Ocean. This index is the first to use unfiltered OLR observations and so does not specifically isolate intraseasonal periods. A composite NPISO life cycle based on this index is similar to previous composites in OLR and surface winds, demonstrating that the dominance of the intraseasonal variability in the monsoon climate system eliminates the need for more complex methods (e.g., time filtering or EOF analysis) to identify the NPISO. This study is also among the first to examine the NPISO using a long-period record of high-resolution sea surface temperatures (SSTs) from the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager. Application of this index to those SSTs demonstrates that SST anomalies exist in near quadrature with convection, as suggested by recent coupled model studies. Analysis of the phase relationships between atmospheric fields and SSTs indicates that the atmosphere likely forced the SST anomalies. The results of this lag-correlation analysis suggest that the oscillation serves as its own most reliable—and perhaps only—predictor, and that signals preceding an NPISO event appear first over the Indian subcontinent, not the equatorial Indian Ocean where the events originate.

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On the Relationship between North Atlantic Sea Surface Temperatures and U.S. Hurricane Landfall Risk

Journal of Applied Meteorology and Climatology ◽

10.1175/2008jamc1871.1 ◽

2009 ◽

Vol 48 (1) ◽

pp. 111-129 ◽

Cited By ~ 26

Author(s):

Peter S. Dailey ◽

Gerhard Zuba ◽

Greta Ljung ◽

Ioana M. Dima ◽

Jayanta Guin

Keyword(s):

General Circulation ◽

Gulf Coast ◽

Ocean Basin ◽

Sea Surface ◽

Physical Analysis ◽

Sea Surface Temperatures ◽

Surface Temperatures ◽

Complete Life Cycle ◽

The Relationship ◽

The U.S

Abstract In the recent literature, considerable attention has been paid to the relationship between climate signals and tropical cyclone activity. Much of the research has focused on Atlantic Ocean basin activity while less attention has been given to landfall frequency and the geographic distribution of risk to life and property. However, recent active seasons like 2004 and 2005 and the resulting damage and economic loss have generated significant interest in the relationship between climate and landfall risk. This study focuses on sea surface temperatures (SST) and examines modulation of landfall activity occurring in anomalously warm-SST seasons. The objective of the study is to evaluate the effect of warmer ocean conditions on U.S. landfall risk. The study is broken into two parts–—statistical and physical. The statistical analysis categorizes historical hurricane seasons as either warm or cool and then estimates shifts in landfall frequency under these two climate modes. The analysis is carried out for overall U.S. landfall risk and then for logical subregions along the U.S. coastline. The climatological behavior for warm-SST conditions is developed across the intensity spectrum, from weak tropical storms to major hurricanes, using wind speed as an intensity measure. The analysis suggests that landfall risk is sensitive to SST conditions but that sensitivity varies by region and intensity. The uncertainty associated with these estimates is discussed. The physical analysis is carried out to understand better why landfall risk is not affected uniformly along the U.S. coastline and to reinforce the reasonability of the statistical results. The study involves a detailed examination of the complete life cycle of historical storms. Results indicate that storms making landfall along the East Coast have different genesis and intensification characteristics relative to storms making landfall along the Gulf Coast. As SSTs warm, the genesis pattern shifts, greatly influencing regional landfall risk. Further, hurricane landfalls may react not only to warm-SST conditions, but also to the effect of ocean temperature anomalies on the atmosphere’s general circulation. There are implications that complex feedback mechanisms play a role in modulating the probability of landfall, especially from certain parts of the Atlantic basin. Such physical theories provide added confidence in statistical estimates of elevated risk for certain breeds of tropical cyclones.

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