Improved sea level record over the satellite altimetry era (1993–2010) from the Climate Change Initiative Project

Abstract. Sea level is one of the 50 Essential Climate Variables (ECVs) listed by the Global Climate Observing System (GCOS) in climate change monitoring. In the last two decades, sea level has been routinely measured from space using satellite altimetry techniques. In order to address a number of important scientific questions such as: "Is sea level rise accelerating?", "Can we close the sea level budget?", "What are the causes of the regional and interannual variability?", "Can we already detect the anthropogenic forcing signature and separate it from the internal/natural climate variability?", and "What are the coastal impacts of sea level rise?", the accuracy of altimetry-based sea level records at global and regional scales needs to be significantly improved. For example, the global mean and regional sea level trend uncertainty should become better than 0.3 and 0.5 mm year−1, respectively (currently of 0.6 and 1–2 mm year−1). Similarly, interannual global mean sea level variations (currently uncertain to 2–3 mm) need to be monitored with better accuracy. In this paper, we present various respective data improvements achieved within the European Space Agency (ESA) Climate Change Initiative (ESA CCI) project on "Sea Level" during its first phase (2010–2013), using multi-mission satellite altimetry data over the 1993–2010 time span. In a first step, using a new processing system with dedicated algorithms and adapted data processing strategies, an improved set of sea level products has been produced. The main improvements include: reduction of orbit errors and wet/dry atmospheric correction errors, reduction of instrumental drifts and bias, inter-calibration biases, intercalibration between missions and combination of the different sea level data sets, and an improvement of the reference mean sea surface. We also present preliminary independent validations of the SL_cci products, based on tide gauges comparison and sea level budget closure approach, as well as comparisons with ocean re-analyses and climate model outputs.

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Improved sea level record over the satellite altimetry era (1993–2010) from the Climate Change Initiative project

Ocean Science ◽

10.5194/os-11-67-2015 ◽

2015 ◽

Vol 11 (1) ◽

pp. 67-82 ◽

Cited By ~ 124

Author(s):

M. Ablain ◽

A. Cazenave ◽

G. Larnicol ◽

M. Balmaseda ◽

P. Cipollini ◽

...

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Satellite Altimetry ◽

Climate Model ◽

Atmospheric Correction ◽

European Space Agency ◽

Processing System ◽

Change Initiative ◽

Global Mean

Abstract. Sea level is one of the 50 Essential Climate Variables (ECVs) listed by the Global Climate Observing System (GCOS) in climate change monitoring. In the past two decades, sea level has been routinely measured from space using satellite altimetry techniques. In order to address a number of important scientific questions such as "Is sea level rise accelerating?", "Can we close the sea level budget?", "What are the causes of the regional and interannual variability?", "Can we already detect the anthropogenic forcing signature and separate it from the internal/natural climate variability?", and "What are the coastal impacts of sea level rise?", the accuracy of altimetry-based sea level records at global and regional scales needs to be significantly improved. For example, the global mean and regional sea level trend uncertainty should become better than 0.3 and 0.5 mm year−1, respectively (currently 0.6 and 1–2 mm year−1). Similarly, interannual global mean sea level variations (currently uncertain to 2–3 mm) need to be monitored with better accuracy. In this paper, we present various data improvements achieved within the European Space Agency (ESA) Climate Change Initiative (ESA CCI) project on "Sea Level" during its first phase (2010–2013), using multi-mission satellite altimetry data over the 1993–2010 time span. In a first step, using a new processing system with dedicated algorithms and adapted data processing strategies, an improved set of sea level products has been produced. The main improvements include: reduction of orbit errors and wet/dry atmospheric correction errors, reduction of instrumental drifts and bias, intercalibration biases, intercalibration between missions and combination of the different sea level data sets, and an improvement of the reference mean sea surface. We also present preliminary independent validations of the SL_cci products, based on tide gauges comparison and a sea level budget closure approach, as well as comparisons with ocean reanalyses and climate model outputs.

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Estimating Relative and Absolute Sea Level Rise at Ny-Ålesundwith satellite altimetry and in-situ observations

10.5194/egusphere-egu21-2836 ◽

2021 ◽

Author(s):

Stefano Vignudelli ◽

Francesco De Biasio

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Satellite Altimetry ◽

Adriatic Sea ◽

Tide Gauge ◽

European Space Agency ◽

Data Sets ◽

Space Agency ◽

Along Track

Consistent and long-term satellite-based data-sets to study climate-scale variations of sea level globally and in the coastal zone are available nowadays. Two altimetry data-sets were recently produced: the first one is generated by the European Space Agency&#8217;s (ESA) Sea Level Climate Change Initiative (SL_CCI) over a grid of 0.25 x 0.25 degrees, merging and homogenizing the various available satellite altimetry missions. The second one is a climate-oriented altimeter sea level product that started in the framework of the European Copernicus Climate Change Service (C3S), and is now released as daily-means over a grid of 0.25 x 0.25 degrees, covering the global ocean since 1993 to present. Both reach in the Arctic the latitude of 81.5 N degrees. Therefore, these new altimetry products cover the coastal area surrounding Ny-&#197;lesund (Svalbard Islands, Norway), where a tide gauge station is active since 1976. Near the Svalbard coasts also the along track surface elevations of the CryoSat-2 mission are made available through the European Space Agency&#8217;s Grid Processing on Demand (G-POD) for Earth Observation Applications facility.In this study, we compare sea level measurements from the Ny-&#197;lesund tide gauge with the climate-oriented altimeter sea level gridded products (SL_CCI and C3S) and with the along track data from the only CryoSat-2 mission. This study has three objectives: 1) to assess the performances of the gridded data moving from offshore to near coasts; 2) to explore how the synergy with along track high resolution CryoSat-2 data might help to detail the sea ice impact on the observation of relative and absolute sea level rise around Svalbard; 3) to verify if the differences between satellite altimetry and tide gauges can be used as a proxy of vertical ground movement in the study area by adopting the approaches elaborated in Vignudelli et al. [2018] and De Biasio et al. [2020] that can be validated with ground vertical displacements estimated using Global Positioning System (GPS) data from the stations close to Ny-&#197;lesund.&#160;REFERENCESVignudelli, S., De Biasio, F., Scozzari, A. Zecchetto, S., and Papa, A. (2019): Sea Level Trends and Variability in the Adriatic Sea and Around Venice, Proceedings of the International Review Workshop on Satellite Altimetry Cal/Val Activities and Applications, 23-26 April 2018, Chania, Crete, Greece. DOI:10.1007/1345_2018_51De Biasio, F.; Baldin, G.; Vignudelli, S. Revisiting Vertical Land Motion and Sea Level Trends in the Northeastern Adriatic Sea Using Satellite Altimetry and Tide Gauge Data. J. Mar. Sci. Eng. 2020, 8, 949. DOI:10.3390/jmse8110949

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An Assessment of Global Macroeconomic Impacts Caused by Sea Level Rise Using the Framework of Shared Socioeconomic Pathways and Representative Concentration Pathways

Sustainability ◽

10.3390/su12093737 ◽

2020 ◽

Vol 12 (9) ◽

pp. 3737

Author(s):

Osamu Nishiura ◽

Makoto Tamura ◽

Shinichiro Fujimori ◽

Kiyoshi Takahashi ◽

Junya Takakura ◽

...

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Low Income ◽

Temperature Increase ◽

General Circulation ◽

Economic Losses ◽

Global Mean Temperature ◽

Mean Temperature ◽

Global Mean

Coastal areas provide important services and functions for social and economic activities. Damage due to sea level rise (SLR) is one of the serious problems anticipated and caused by climate change. In this study, we assess the global economic impact of inundation due to SLR by using a computable general equilibrium (CGE) model that incorporates detailed coastal damage information. The scenario analysis considers multiple general circulation models, socioeconomic assumptions, and stringency of climate change mitigation measures. We found that the global household consumption loss proportion will be 0.045%, with a range of 0.027−0.066%, in 2100. Socioeconomic assumptions cause a difference in the loss proportion of up to 0.035% without greenhouse gas (GHG) emissions mitigation, the so-called baseline scenarios. The range of the loss proportion among GHG emission scenarios is smaller than the differences among the socioeconomic assumptions. We also observed large regional variations and, in particular, the consumption losses in low-income countries are, relatively speaking, larger than those in high-income countries. These results indicate that, even if we succeed in stabilizing the global mean temperature increase below 2 °C, economic losses caused by SLR will inevitably happen to some extent, which may imply that keeping the global mean temperature increase below 1.5 °C would be worthwhile to consider.

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Effect of the processing methodology on satellite altimetry-based global mean sea level rise over the Jason-1 operating period

Journal of Geodesy ◽

10.1007/s00190-013-0687-3 ◽

2013 ◽

Vol 88 (4) ◽

pp. 351-361 ◽

Cited By ~ 27

Author(s):

Olivier Henry ◽

Michael Ablain ◽

Benoit Meyssignac ◽

Anny Cazenave ◽

Dallas Masters ◽

...

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Satellite Altimetry ◽

Operating Period ◽

Mean Sea Level ◽

Global Mean Sea Level ◽

Global Mean

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A scaling approach to project regional sea level rise and its uncertainties

Earth System Dynamics ◽

10.5194/esd-4-11-2013 ◽

2013 ◽

Vol 4 (1) ◽

pp. 11-29 ◽

Cited By ~ 77

Author(s):

M. Perrette ◽

F. Landerer ◽

R. Riva ◽

K. Frieler ◽

M. Meinshausen

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

General Circulation ◽

Ice Sheets ◽

General Circulation Models ◽

Ice Melt ◽

Probabilistic Forecasts ◽

Regional Sea Level ◽

Global Mean

Abstract. Climate change causes global mean sea level to rise due to thermal expansion of seawater and loss of land ice from mountain glaciers, ice caps and ice sheets. Locally, sea level can strongly deviate from the global mean rise due to changes in wind and ocean currents. In addition, gravitational adjustments redistribute seawater away from shrinking ice masses. However, the land ice contribution to sea level rise (SLR) remains very challenging to model, and comprehensive regional sea level projections, which include appropriate gravitational adjustments, are still a nascent field (Katsman et al., 2011; Slangen et al., 2011). Here, we present an alternative approach to derive regional sea level changes for a range of emission and land ice melt scenarios, combining probabilistic forecasts of a simple climate model (MAGICC6) with the new CMIP5 general circulation models. The contribution from ice sheets varies considerably depending on the assumptions for the ice sheet projections, and thus represents sizeable uncertainties for future sea level rise. However, several consistent and robust patterns emerge from our analysis: at low latitudes, especially in the Indian Ocean and Western Pacific, sea level will likely rise more than the global mean (mostly by 10–20%). Around the northeastern Atlantic and the northeastern Pacific coasts, sea level will rise less than the global average or, in some rare cases, even fall. In the northwestern Atlantic, along the American coast, a strong dynamic sea level rise is counteracted by gravitational depression due to Greenland ice melt; whether sea level will be above- or below-average will depend on the relative contribution of these two factors. Our regional sea level projections and the diagnosed uncertainties provide an improved basis for coastal impact analysis and infrastructure planning for adaptation to climate change.

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An improved and homogeneous altimeter sea level record from the ESA Climate Change Initiative

Earth System Science Data ◽

10.5194/essd-10-281-2018 ◽

2018 ◽

Vol 10 (1) ◽

pp. 281-301 ◽

Cited By ~ 67

Author(s):

Jean-François Legeais ◽

Michaël Ablain ◽

Lionel Zawadzki ◽

Hao Zuo ◽

Johnny A. Johannessen ◽

...

Keyword(s):

Climate Change ◽

Sea Level ◽

Global Climate ◽

European Space Agency ◽

Bias Reduction ◽

Second Phase ◽

Change Initiative ◽

Internal Validation ◽

Spatial And Temporal Scales ◽

Space Agency

Abstract. Sea level is a very sensitive index of climate change since it integrates the impacts of ocean warming and ice mass loss from glaciers and the ice sheets. Sea level has been listed as an essential climate variable (ECV) by the Global Climate Observing System (GCOS). During the past 25 years, the sea level ECV has been measured from space by different altimetry missions that have provided global and regional observations of sea level variations. As part of the Climate Change Initiative (CCI) program of the European Space Agency (ESA) (established in 2010), the Sea Level project (SL_cci) aimed to provide an accurate and homogeneous long-term satellite-based sea level record. At the end of the first phase of the project (2010–2013), an initial version (v1.1) of the sea level ECV was made available to users (Ablain et al., 2015). During the second phase of the project (2014–2017), improved altimeter standards were selected to produce new sea level products (called SL_cci v2.0) based on nine altimeter missions for the period 1993–2015 (https://doi.org/10.5270/esa-sea_level_cci-1993_2015-v_2.0-201612; Legeais and the ESA SL_cci team, 2016c). Corresponding orbit solutions, geophysical corrections and altimeter standards used in this v2.0 dataset are described in detail in Quartly et al. (2017). The present paper focuses on the description of the SL_cci v2.0 ECV and associated uncertainty and discusses how it has been validated. Various approaches have been used for the quality assessment such as internal validation, comparisons with sea level records from other groups and with in situ measurements, sea level budget closure analyses and comparisons with model outputs. Compared with the previous version of the sea level ECV, we show that use of improved geophysical corrections, careful bias reduction between missions and inclusion of new altimeter missions lead to improved sea level products with reduced uncertainties on different spatial and temporal scales. However, there is still room for improvement since the uncertainties remain larger than the GCOS requirements (GCOS, 2011). Perspectives on subsequent evolution are also discussed.

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Estimating Vertical Land Motion in Northern Adriatic Sea with Coastal Altimetry and In Situ Observations

10.5194/egusphere-egu2020-9754 ◽

2020 ◽

Author(s):

Francesco De Biasio ◽

Stefano Vignudelli ◽

Giorgio Baldin

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Mediterranean Sea ◽

Sea Level ◽

Coastal Zone ◽

Satellite Altimetry ◽

Data Sets ◽

Tide Gauges ◽

The Mediterranean

The European Space Agency, in the framework of the Sea Level Climate Change Initiative (SL_CCI), is developing consistent and long-term satellite-based data-sets to study climate-scale variations of sea level globally and in the coastal zone. Two altimetry data-sets were recently produced. The first product is generated over a grid of 0.25x0.25 degrees, merging and homogenizing the various satellite altimetry missions. The second product that is still experimental is along track over a grid of 0.35 km. An operational production of climate-oriented altimeter sea level products has just started in the framework of the European Copernicus Climate Change Service (C3S) and a daily-mean product is now available over a grid of 0.125x0.125 degrees covering the global ocean since 1993 to present.We made a comparison of the SL_CCI satellite altimetry dataset with sea level time series at selected tide gauges in the Mediterranean Sea, focusing on Venice and Trieste. There, the coast is densely covered by civil settlements and industrial areas with a strongly rooted seaside tourism, and tides and storm-related surges reach higher levels than in most of the Mediterranean Sea, causing damages and casualties as in the recent storm of November 12th, 2019: the second higher water registered in Venice since 1872. Moreover, in the Venice area the ground displacements exhibit clear negative trends which deepen the effects of the absolute sea level rise.Several authors have pointed out the synergy between satellite altimetry and tide gauges to corroborate evidences of ground displacements. Our contribution aims at understanding the role played by subsidence, estimated by the diffence between coastal altimetry and in situ measurements, on the local sea level rise. A partial validation of these estimates has been made against GPS-derived values, in order to distinguish the contributions of subsidence and eustatism. This work will contribute to identify problems and challenges to extend the sea level climate record to the coastal zone with quality comparable to the open ocean, and also to assess the suitability of altimeter-derived absolute sea levels as a tool to estimate subsidence from tide gauge measurement in places where permanent GPS receivers are not available.

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Carbon Dioxide Emission Pathways Avoiding Dangerous Ocean Impacts

Weather Climate and Society ◽

10.1175/wcas-d-11-00030.1 ◽

2012 ◽

Vol 4 (3) ◽

pp. 212-229 ◽

Cited By ~ 1

Author(s):

K. Kvale ◽

K. Zickfeld ◽

T. Bruckner ◽

K. J. Meissner ◽

K. Tanaka ◽

...

Keyword(s):

Greenhouse Gases ◽

Ocean Acidification ◽

Sea Level Rise ◽

Sea Level ◽

Co2 Emissions ◽

Climate Model ◽

Ice Sheet ◽

Global Mean Temperature ◽

Mean Temperature ◽

Global Mean

Abstract Anthropogenic emissions of greenhouse gases could lead to undesirable effects on oceans in coming centuries. Drawing on recommendations published by the German Advisory Council on Global Change, levels of unacceptable global marine change (so-called guardrails) are defined in terms of global mean temperature, sea level rise, and ocean acidification. A global-mean climate model [the Aggregated Carbon Cycle, Atmospheric Chemistry and Climate Model (ACC2)] is coupled with an economic module [taken from the Dynamic Integrated Climate–Economy Model (DICE)] to conduct a cost-effectiveness analysis to derive CO2 emission pathways that both minimize abatement costs and are compatible with these guardrails. Additionally, the “tolerable windows approach” is used to calculate a range of CO2 emissions paths that obey the guardrails as well as a restriction on mitigation rate. Prospects of meeting the global mean temperature change guardrail (2° and 0.2°C decade−1 relative to preindustrial) depend strongly on assumed values for climate sensitivity: at climate sensitivities >3°C the guardrail cannot be attained under any CO2 emissions reduction strategy without mitigation of non-CO2 greenhouse gases. The ocean acidification guardrail (0.2 unit pH decline relative to preindustrial) is less restrictive than the absolute temperature guardrail at climate sensitivities >2.5°C but becomes more constraining at lower climate sensitivities. The sea level rise and rate of rise guardrails (1 m and 5 cm decade−1) are substantially less stringent for ice sheet sensitivities derived in the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report, but they may already be committed to violation if ice sheet sensitivities consistent with semiempirical sea level rise projections are assumed.

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A method for assessing the coastline recession due to the sea level rise by assuming stationary wind-wave climate

Oceanological and Hydrobiological Studies ◽

10.1515/ohs-2015-0035 ◽

2015 ◽

Vol 44 (3) ◽

Cited By ~ 8

Author(s):

Junjie Deng ◽

Jan Harff ◽

Semjon Schimanke ◽

H. E. Markus Meier

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Linear Relationship ◽

Sea Level ◽

Climate Model ◽

Wind Wave ◽

Dynamic Equilibrium ◽

Wave Climate ◽

Sediment Budget ◽

Least Square

AbstractThe method introduced in this study for future projection of coastline changes hits the vital need of communicating the potential climate change impact on the coast in the 21th century. A quantitative method called the Dynamic Equilibrium Shore Model (DESM) has been developed to hindcast historical sediment mass budgets and to reconstruct a paleo Digital Elevation Model (DEM). The forward mode of the DESM model relies on paleo-scenarios reconstructed by the DESM model assuming stationary wind-wave climate. A linear relationship between the sea level, coastline changes and sediment budget is formulated and proven by the least square regression method. In addition to its forward prediction of coastline changes, this linear relationship can also estimate the sediment budget by using the information on the coastline and relative sea level changes. Wind climate change is examined based on regional climate model data. Our projections for the end of the 21st century suggest that the wind and wave climates in the southern Baltic Sea may not change compared to present conditions and that the investigated coastline along the Pomeranian Bay may retreat from 10 to 100 m depending on the location and on the sea level rise which was assumed to be in the range of 0.12 to 0.24 m.

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The transient sensitivity of sea level rise

Ocean Science ◽

10.5194/os-17-181-2021 ◽

2021 ◽

Vol 17 (1) ◽

pp. 181-186

Author(s):

Aslak Grinsted ◽

Jens Hesselbjerg Christensen

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Carbon Dioxide Emissions ◽

Radiative Forcing ◽

Climate Models ◽

Climate Model ◽

Greenhouse Gas Emission ◽

Rate Of Change ◽

Intergovernmental Panel ◽

Global Mean

Abstract. Recent assessments from the Intergovernmental Panel on Climate Change (IPCC) imply that global mean sea level is unlikely to rise more than about 1.1 m within this century but will increase further beyond 2100. Even within the most intensive future anthropogenic greenhouse gas emission scenarios, higher levels are assessed to be unlikely. However, some studies conclude that considerably greater sea level rise could be realized, and a number of experts assign a substantially higher likelihood of such a future. To understand this discrepancy, it would be useful to have scenario-independent metrics that can be compared between different approaches. The concept of a transient climate sensitivity has proven to be useful to compare the global mean temperature response of climate models to specific radiative forcing scenarios. Here, we introduce a similar metric for sea level response. By analyzing the mean rate of change in sea level (not sea level itself), we identify a nearly linear relationship with global mean surface temperature (and therefore accumulated carbon dioxide emissions) both in model projections and in observations on a century scale. This motivates us to define the “transient sea level sensitivity” as the increase in the sea level rate associated with a given warming in units of meters per century per kelvin. We find that future projections estimated on climate model responses fall below extrapolation based on recent observational records. This comparison suggests that the likely upper level of sea level projections in recent IPCC reports would be too low.

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