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Ruth Reef - One of the best experts on this subject based on the ideXlab platform.
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future response of global coastal wetlands to Sea Level Rise
Nature, 2018Co-Authors: T Spencer, Mark Schuerch, Daniel Lincke, Matthew L Kirwan, Stijn Temmerman, Claudia Wolff, Chris Mcowen, Mark D Pickering, Ruth ReefAbstract:The response of coastal wetlands to Sea-Level Rise during the twenty-first century remains uncertain. Global-scale projections suggest that between 20 and 90 per cent (for low and high Sea-Level Rise scenarios, respectively) of the present-day coastal wetland area will be lost, which will in turn result in the loss of biodiversity and highly valued ecosystem services1-3. These projections do not necessarily take into account all essential geomorphological4-7 and socio-economic system feedbacks8. Here we present an integrated global modelling approach that considers both the ability of coastal wetlands to build up vertically by sediment accretion, and the accommodation space, namely, the vertical and lateral space available for fine sediments to accumulate and be colonized by wetland vegetation. We use this approach to assess global-scale changes in coastal wetland area in response to global Sea-Level Rise and anthropogenic coastal occupation during the twenty-first century. On the basis of our simulations, we find that, globally, rather than losses, wetland gains of up to 60 per cent of the current area are possible, if more than 37 per cent (our upper estimate for current accommodation space) of coastal wetlands have sufficient accommodation space, and sediment supply remains at present Levels. In contrast to previous studies1-3, we project that until 2100, the loss of global coastal wetland area will range between 0 and 30 per cent, assuming no further accommodation space in addition to current Levels. Our simulations suggest that the resilience of global wetlands is primarily driven by the availability of accommodation space, which is strongly influenced by the building of anthropogenic infrastructure in the coastal zone and such infrastructure is expected to change over the twenty-first century. Rather than being an inevitable consequence of global Sea-Level Rise, our findings indicate that large-scale loss of coastal wetlands might be avoidable, if sufficient additional accommodation space can be created through careful nature-based adaptation solutions to coastal management.
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future response of global coastal wetlands to Sea Level Rise
Nature, 2018Co-Authors: T Spencer, Mark Schuerch, Daniel Lincke, Matthew L Kirwan, Stijn Temmerman, Claudia Wolff, Chris Mcowen, Mark D Pickering, Ruth ReefAbstract:The response of coastal wetlands to Sea-Level Rise during the twenty-first century remains uncertain. Global-scale projections suggest that between 20 and 90 per cent (for low and high Sea-Level Rise scenarios, respectively) of the present-day coastal wetland area will be lost, which will in turn result in the loss of biodiversity and highly valued ecosystem services1–3. These projections do not necessarily take into account all essential geomorphological4–7 and socio-economic system feedbacks8. Here we present an integrated global modelling approach that considers both the ability of coastal wetlands to build up vertically by sediment accretion, and the accommodation space, namely, the vertical and lateral space available for fine sediments to accumulate and be colonized by wetland vegetation. We use this approach to assess global-scale changes in coastal wetland area in response to global Sea-Level Rise and anthropogenic coastal occupation during the twenty-first century. On the basis of our simulations, we find that, globally, rather than losses, wetland gains of up to 60 per cent of the current area are possible, if more than 37 per cent (our upper estimate for current accommodation space) of coastal wetlands have sufficient accommodation space, and sediment supply remains at present Levels. In contrast to previous studies1–3, we project that until 2100, the loss of global coastal wetland area will range between 0 and 30 per cent, assuming no further accommodation space in addition to current Levels. Our simulations suggest that the resilience of global wetlands is primarily driven by the availability of accommodation space, which is strongly influenced by the building of anthropogenic infrastructure in the coastal zone and such infrastructure is expected to change over the twenty-first century. Rather than being an inevitable consequence of global Sea-Level Rise, our findings indicate that large-scale loss of coastal wetlands might be avoidable, if sufficient additional accommodation space can be created through careful nature-based adaptation solutions to coastal management. A global modelling approach shows that in response to Rises in global Sea Level, gains of up to 60% in coastal wetland areas are possible, if appropriate coastal management solutions are developed to help support wetland resilience.
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global coastal wetland change under Sea Level Rise and related stresses the diva wetland change model
Global and Planetary Change, 2016Co-Authors: T Spencer, Robert J Nicholls, Mark Schuerch, Jochen Hinkel, Daniel Lincke, Athanasios T Vafeidis, Ruth Reef, Loraine Mcfadden, Sally BrownAbstract:The Dynamic Interactive Vulnerability Assessment Wetland Change Model (DIVA_WCM) compRises a dataset of contemporary global coastal wetland stocks (estimated at 756 × 103 km2 (in 2011)), mapped to a one-dimensional global database, and a model of the macro-scale controls on wetland response to Sea-Level Rise. Three key drivers of wetland response to Sea-Level Rise are considered: 1) rate of Sea-Level Rise relative to tidal range; 2) lateral accommodation space; and 3) sediment supply. The model is tuned by expert knowledge, parameteRised with quantitative data where possible, and validated against mapping associated with two large-scale mangrove and saltmarsh vulnerability studies. It is applied across 12,148 coastal segments (mean length 85 km) to the year 2100. The model provides better-informed macro-scale projections of likely patterns of future coastal wetland losses across a range of Sea-Level Rise scenarios and varying assumptions about the construction of coastal dikes to prevent Sea flooding (as dikes limit lateral accommodation space and cause coastal squeeze). With 50 cm of Sea-Level Rise by 2100, the model predicts a loss of 46–59% of global coastal wetland stocks. A global coastal wetland loss of 78% is estimated under high Sea-Level Rise (110 cm by 2100) accompanied by maximum dike construction. The primary driver for high vulnerability of coastal wetlands to Sea-Level Rise is coastal squeeze, a consequence of long-term coastal protection strategies. Under low Sea-Level Rise (29 cm by 2100) losses do not exceed ca. 50% of the total stock, even for the same adverse dike construction assumptions. The model results confirm that the widespread paradigm that wetlands subject to a micro-tidal regime are likely to be more vulnerable to loss than macro-tidal environments. Countering these potential losses will require both climate mitigation (a global response) to minimise Sea-Level Rise and maximisation of accommodation space and sediment supply (a regional response) on low-lying coasts.
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the vulnerability of indo pacific mangrove forests to Sea Level Rise
Nature, 2015Co-Authors: Catherine E. Lovelock, Donald R. Cahoon, Ken W Krauss, Daniel A. Friess, Ruth Reef, Glenn R Guntenspergen, Kerrylee Rogers, Megan L Saunders, Frida SidikAbstract:Sea-Level Rise can threaten the long-term sustainability of coastal communities and valuable ecosystems such as coral reefs, salt marshes and mangroves. Mangrove forests have the capacity to keep pace with Sea-Level Rise and to avoid inundation through vertical accretion of sediments, which allows them to maintain wetland soil elevations suitable for plant growth. The Indo-Pacific region holds most of the world's mangrove forests, but sediment delivery in this region is declining, owing to anthropogenic activities such as damming of rivers. This decline is of particular concern because the Indo-Pacific region is expected to have variable, but high, rates of future Sea-Level Rise. Here we analyse recent trends in mangrove surface elevation changes across the Indo-Pacific region using data from a network of surface elevation table instruments. We find that sediment availability can enable mangrove forests to maintain rates of soil-surface elevation gain that match or exceed that of Sea-Level Rise, but for 69 per cent of our study sites the current rate of Sea-Level Rise exceeded the soil surface elevation gain. We also present a model based on our field data, which suggests that mangrove forests at sites with low tidal range and low sediment supply could be submerged as early as 2070.
Mark Schuerch - One of the best experts on this subject based on the ideXlab platform.
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future response of global coastal wetlands to Sea Level Rise
Nature, 2018Co-Authors: T Spencer, Mark Schuerch, Daniel Lincke, Matthew L Kirwan, Stijn Temmerman, Claudia Wolff, Chris Mcowen, Mark D Pickering, Ruth ReefAbstract:The response of coastal wetlands to Sea-Level Rise during the twenty-first century remains uncertain. Global-scale projections suggest that between 20 and 90 per cent (for low and high Sea-Level Rise scenarios, respectively) of the present-day coastal wetland area will be lost, which will in turn result in the loss of biodiversity and highly valued ecosystem services1–3. These projections do not necessarily take into account all essential geomorphological4–7 and socio-economic system feedbacks8. Here we present an integrated global modelling approach that considers both the ability of coastal wetlands to build up vertically by sediment accretion, and the accommodation space, namely, the vertical and lateral space available for fine sediments to accumulate and be colonized by wetland vegetation. We use this approach to assess global-scale changes in coastal wetland area in response to global Sea-Level Rise and anthropogenic coastal occupation during the twenty-first century. On the basis of our simulations, we find that, globally, rather than losses, wetland gains of up to 60 per cent of the current area are possible, if more than 37 per cent (our upper estimate for current accommodation space) of coastal wetlands have sufficient accommodation space, and sediment supply remains at present Levels. In contrast to previous studies1–3, we project that until 2100, the loss of global coastal wetland area will range between 0 and 30 per cent, assuming no further accommodation space in addition to current Levels. Our simulations suggest that the resilience of global wetlands is primarily driven by the availability of accommodation space, which is strongly influenced by the building of anthropogenic infrastructure in the coastal zone and such infrastructure is expected to change over the twenty-first century. Rather than being an inevitable consequence of global Sea-Level Rise, our findings indicate that large-scale loss of coastal wetlands might be avoidable, if sufficient additional accommodation space can be created through careful nature-based adaptation solutions to coastal management. A global modelling approach shows that in response to Rises in global Sea Level, gains of up to 60% in coastal wetland areas are possible, if appropriate coastal management solutions are developed to help support wetland resilience.
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future response of global coastal wetlands to Sea Level Rise
Nature, 2018Co-Authors: T Spencer, Mark Schuerch, Daniel Lincke, Matthew L Kirwan, Stijn Temmerman, Claudia Wolff, Chris Mcowen, Mark D Pickering, Ruth ReefAbstract:The response of coastal wetlands to Sea-Level Rise during the twenty-first century remains uncertain. Global-scale projections suggest that between 20 and 90 per cent (for low and high Sea-Level Rise scenarios, respectively) of the present-day coastal wetland area will be lost, which will in turn result in the loss of biodiversity and highly valued ecosystem services1-3. These projections do not necessarily take into account all essential geomorphological4-7 and socio-economic system feedbacks8. Here we present an integrated global modelling approach that considers both the ability of coastal wetlands to build up vertically by sediment accretion, and the accommodation space, namely, the vertical and lateral space available for fine sediments to accumulate and be colonized by wetland vegetation. We use this approach to assess global-scale changes in coastal wetland area in response to global Sea-Level Rise and anthropogenic coastal occupation during the twenty-first century. On the basis of our simulations, we find that, globally, rather than losses, wetland gains of up to 60 per cent of the current area are possible, if more than 37 per cent (our upper estimate for current accommodation space) of coastal wetlands have sufficient accommodation space, and sediment supply remains at present Levels. In contrast to previous studies1-3, we project that until 2100, the loss of global coastal wetland area will range between 0 and 30 per cent, assuming no further accommodation space in addition to current Levels. Our simulations suggest that the resilience of global wetlands is primarily driven by the availability of accommodation space, which is strongly influenced by the building of anthropogenic infrastructure in the coastal zone and such infrastructure is expected to change over the twenty-first century. Rather than being an inevitable consequence of global Sea-Level Rise, our findings indicate that large-scale loss of coastal wetlands might be avoidable, if sufficient additional accommodation space can be created through careful nature-based adaptation solutions to coastal management.
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global coastal wetland change under Sea Level Rise and related stresses the diva wetland change model
Global and Planetary Change, 2016Co-Authors: T Spencer, Robert J Nicholls, Mark Schuerch, Jochen Hinkel, Daniel Lincke, Athanasios T Vafeidis, Ruth Reef, Loraine Mcfadden, Sally BrownAbstract:The Dynamic Interactive Vulnerability Assessment Wetland Change Model (DIVA_WCM) compRises a dataset of contemporary global coastal wetland stocks (estimated at 756 × 103 km2 (in 2011)), mapped to a one-dimensional global database, and a model of the macro-scale controls on wetland response to Sea-Level Rise. Three key drivers of wetland response to Sea-Level Rise are considered: 1) rate of Sea-Level Rise relative to tidal range; 2) lateral accommodation space; and 3) sediment supply. The model is tuned by expert knowledge, parameteRised with quantitative data where possible, and validated against mapping associated with two large-scale mangrove and saltmarsh vulnerability studies. It is applied across 12,148 coastal segments (mean length 85 km) to the year 2100. The model provides better-informed macro-scale projections of likely patterns of future coastal wetland losses across a range of Sea-Level Rise scenarios and varying assumptions about the construction of coastal dikes to prevent Sea flooding (as dikes limit lateral accommodation space and cause coastal squeeze). With 50 cm of Sea-Level Rise by 2100, the model predicts a loss of 46–59% of global coastal wetland stocks. A global coastal wetland loss of 78% is estimated under high Sea-Level Rise (110 cm by 2100) accompanied by maximum dike construction. The primary driver for high vulnerability of coastal wetlands to Sea-Level Rise is coastal squeeze, a consequence of long-term coastal protection strategies. Under low Sea-Level Rise (29 cm by 2100) losses do not exceed ca. 50% of the total stock, even for the same adverse dike construction assumptions. The model results confirm that the widespread paradigm that wetlands subject to a micro-tidal regime are likely to be more vulnerable to loss than macro-tidal environments. Countering these potential losses will require both climate mitigation (a global response) to minimise Sea-Level Rise and maximisation of accommodation space and sediment supply (a regional response) on low-lying coasts.
Carlfriedrich Schleussner - One of the best experts on this subject based on the ideXlab platform.
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attributing long term Sea Level Rise to paris agreement emission pledges
Proceedings of the National Academy of Sciences of the United States of America, 2019Co-Authors: Alexander Nauels, Matthias Mengel, Carlfriedrich Schleussner, Johannes Gutschow, Malte Meinshausen, Peter U ClarkAbstract:The main contributors to Sea-Level Rise (oceans, glaciers, and ice sheets) respond to climate change on timescales ranging from decades to millennia. A focus on the 21st century thus fails to provide a complete picture of the consequences of anthropogenic greenhouse gas emissions on future Sea-Level Rise and its long-term impacts. Here we identify the committed global mean Sea-Level Rise until 2300 from historical emissions since 1750 and the currently pledged National Determined Contributions (NDC) under the Paris Agreement until 2030. Our results indicate that greenhouse gas emissions over this 280-y period result in about 1 m of committed global mean Sea-Level Rise by 2300, with the NDC emissions from 2016 to 2030 corresponding to around 20 cm or 1/5 of that commitment. We also find that 26 cm (12 cm) of the projected Sea-Level-Rise commitment in 2300 can be attributed to emissions from the top 5 emitting countries (China, United States of America, European Union, India, and Russia) over the 1991-2030 (2016-2030) period. Our findings demonstrate that global and individual country emissions over the first decades of the 21st century alone will cause substantial long-term Sea-Level Rise.
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committed Sea Level Rise under the paris agreement and the legacy of delayed mitigation action
Nature Communications, 2018Co-Authors: Matthias Mengel, Alexander Nauels, Joeri Rogelj, Carlfriedrich SchleussnerAbstract:Sea-Level Rise is a major consequence of climate change that will continue long after emissions of greenhouse gases have stopped. The 2015 Paris Agreement aims at reducing climate-related risks by reducing greenhouse gas emissions to net zero and limiting global-mean temperature increase. Here we quantify the effect of these constraints on global Sea-Level Rise until 2300, including Antarctic ice-sheet instabilities. We estimate median Sea-Level Rise between 0.7 and 1.2 m, if net-zero greenhouse gas emissions are sustained until 2300, varying with the pathway of emissions during this century. Temperature stabilization below 2 °C is insufficient to hold median Sea-Level Rise until 2300 below 1.5 m. We find that each 5-year delay in near-term peaking of CO2 emissions increases median year 2300 Sea-Level Rise estimates by ca. 0.2 m, and extreme Sea-Level Rise estimates at the 95th percentile by up to 1 m. Our results underline the importance of near-term mitigation action for limiting long-term Sea-Level Rise risks.
Matthias Mengel - One of the best experts on this subject based on the ideXlab platform.
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attributing long term Sea Level Rise to paris agreement emission pledges
Proceedings of the National Academy of Sciences of the United States of America, 2019Co-Authors: Alexander Nauels, Matthias Mengel, Carlfriedrich Schleussner, Johannes Gutschow, Malte Meinshausen, Peter U ClarkAbstract:The main contributors to Sea-Level Rise (oceans, glaciers, and ice sheets) respond to climate change on timescales ranging from decades to millennia. A focus on the 21st century thus fails to provide a complete picture of the consequences of anthropogenic greenhouse gas emissions on future Sea-Level Rise and its long-term impacts. Here we identify the committed global mean Sea-Level Rise until 2300 from historical emissions since 1750 and the currently pledged National Determined Contributions (NDC) under the Paris Agreement until 2030. Our results indicate that greenhouse gas emissions over this 280-y period result in about 1 m of committed global mean Sea-Level Rise by 2300, with the NDC emissions from 2016 to 2030 corresponding to around 20 cm or 1/5 of that commitment. We also find that 26 cm (12 cm) of the projected Sea-Level-Rise commitment in 2300 can be attributed to emissions from the top 5 emitting countries (China, United States of America, European Union, India, and Russia) over the 1991-2030 (2016-2030) period. Our findings demonstrate that global and individual country emissions over the first decades of the 21st century alone will cause substantial long-term Sea-Level Rise.
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committed Sea Level Rise under the paris agreement and the legacy of delayed mitigation action
Nature Communications, 2018Co-Authors: Matthias Mengel, Alexander Nauels, Joeri Rogelj, Carlfriedrich SchleussnerAbstract:Sea-Level Rise is a major consequence of climate change that will continue long after emissions of greenhouse gases have stopped. The 2015 Paris Agreement aims at reducing climate-related risks by reducing greenhouse gas emissions to net zero and limiting global-mean temperature increase. Here we quantify the effect of these constraints on global Sea-Level Rise until 2300, including Antarctic ice-sheet instabilities. We estimate median Sea-Level Rise between 0.7 and 1.2 m, if net-zero greenhouse gas emissions are sustained until 2300, varying with the pathway of emissions during this century. Temperature stabilization below 2 °C is insufficient to hold median Sea-Level Rise until 2300 below 1.5 m. We find that each 5-year delay in near-term peaking of CO2 emissions increases median year 2300 Sea-Level Rise estimates by ca. 0.2 m, and extreme Sea-Level Rise estimates at the 95th percentile by up to 1 m. Our results underline the importance of near-term mitigation action for limiting long-term Sea-Level Rise risks.
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future Sea Level Rise constrained by observations and long term commitment
Proceedings of the National Academy of Sciences of the United States of America, 2016Co-Authors: Matthias Mengel, Anders Levermann, Katja Frieler, Alexander Robinson, Ben Marzeion, Ricarda WinkelmannAbstract:Sea Level has been steadily rising over the past century, predominantly due to anthropogenic climate change. The rate of Sea Level Rise will keep increasing with continued global warming, and, even if temperatures are stabilized through the phasing out of greenhouse gas emissions, Sea Level is still expected to Rise for centuries. This will affect coastal areas worldwide, and robust projections are needed to assess mitigation options and guide adaptation measures. Here we combine the equilibrium response of the main Sea Level Rise contributions with their last century's observed contribution to constrain projections of future Sea Level Rise. Our model is calibrated to a set of observations for each contribution, and the observational and climate uncertainties are combined to produce uncertainty ranges for 21st century Sea Level Rise. We project anthropogenic Sea Level Rise of 28-56 cm, 37-77 cm, and 57-131 cm in 2100 for the greenhouse gas concentration scenarios RCP26, RCP45, and RCP85, respectively. Our uncertainty ranges for total Sea Level Rise overlap with the process-based estimates of the Intergovernmental Panel on Climate Change. The "constrained extrapolation" approach generalizes earlier global semiempirical models and may therefore lead to a better understanding of the discrepancies with process-based projections.
Neil J White - One of the best experts on this subject based on the ideXlab platform.
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Sea Level Rise at tropical pacific and indian ocean islands
Global and Planetary Change, 2006Co-Authors: Neil J White, John A Church, J R HunterAbstract:Historical and projected Sea-Levels for islands in the tropical Pacific and Indian oceans are a subject of considerable interest and some controversy. The large variability (e.g. El Nino) signals and the shortness of many of the individual tide-gauge records contribute to uncertainty of historical rates of Sea-Level Rise. Here, we determine rates of Sea-Level Rise from tide gauges in the region. We also examine Sea-Level data from the TOPEX/Poseidon satellite altimeter and from a reconstruction of Sea Level in order to put the sparse (in space and time) tide-gauge data into context. For 1993 to 2001, all the data show large rates of Sea-Level Rise over the western Pacific and eastern Indian Ocean (approaching 30 mm yr −1 ) and Sea-Level falls in the eastern Pacific and western Indian Ocean (approaching −10 mm yr −1 ). Over the region 40°S to 40°N, 30°E to 120°W, the average Rise is about 4 mm yr −1 . For 1950 to 2001, the average Sea-Level Rise (relative to land) from the six longest tide-gauge records is 1.4 mm yr −1 . After correcting for glacial isostatic adjustment and atmospheric pressure effects, this rate is 2.0 mm yr −1 , close to estimates of the global average and regional average rate of Rise. The long tide-gauge records in the equatorial Pacific indicate that the variance of monthly averaged Sea-Level after 1970 is about twice that before 1970. We find no evidence for the fall in Sea Level at the Maldives as postulated by Morner et al. (2004). Our best estimate of relative Sea-Level Rise at Funafuti, Tuvalu is 2±1 mm yr −1 over the period 1950 to 2001. The analysis clearly indicates that Sea-Level in this region is rising. We expect that the continued and increasing rate of Sea-Level Rise and any resulting increase in the frequency or intensity of extreme Sea-Level events will cause serious problems for the inhabitants of some of these islands during the 21st century.
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A 20th century acceleration in global Sea-Level Rise
Geophysical Research Letters, 2006Co-Authors: Jessica A Church, Neil J WhiteAbstract:Multi-century Sea-Level records and climate models indicate an acceleration of Sea-Level Rise, but no 20th century acceleration has previously been detected. A reconstruction of global Sea Level using tide-gauge data from 1950 to 2000 indicates a larger rate of Rise after 1993 and other periods of rapid Sea-Level Rise but no significant acceleration over this period. Here, we extend the reconstruction of global mean Sea Level back to 1870 and find a Sea-Level Rise from January 1870 to December 2004 of 195 mm, a 20th century rate of Sea-Level Rise of 1.7 +/- 0.3 mm yr-1 and a significant acceleration of Sea-Level Rise of 0.013 +/- 0.006 mm yr-2. This acceleration is an important confirmation of climate change simulations which show an acceleration not previously observed. If this acceleration remained constant then the 1990 to 2100 Rise would range from 280 to 340 mm, consistent with projections in the IPCC TAR.
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estimates of the regional distribution of Sea Level Rise over the 1950 2000 period
Journal of Climate, 2004Co-Authors: John A Church, Neil J White, R Coleman, Kurt Lambeck, Jerry X MitrovicaAbstract:Abstract TOPEX/Poseidon satellite altimeter data are used to estimate global empirical orthogonal functions that are then combined with historical tide gauge data to estimate monthly distributions of large-scale Sea Level variability and change over the period 1950–2000. The reconstruction is an attempt to narrow the current broad range of Sea Level Rise estimates, to identify any pattern of regional Sea Level Rise, and to determine any variation in the rate of Sea Level Rise over the 51-yr period. The computed rate of global-averaged Sea Level Rise from the reconstructed monthly time series is 1.8 ± 0.3 mm yr−1. With the decadal variability in the computed global mean Sea Level, it is not possible to detect a significant increase in the rate of Sea Level Rise over the period 1950–2000. A regional pattern of Sea Level Rise is identified. The maximum Sea Level Rise is in the eastern off-equatorial Pacific and there is a minimum along the equator, in the western Pacific, and in the eastern Indian Ocean. A g...
