This statistic shows a ranking of the ten lowest dry land points on earth. The lowest land point is the Dead Sea Depression with an elevation amounting to approximately *** meters below sea level, however, this elevation is an estimate and tends to fluctuate. The shoreline of the Dead Sea is the lowest dry land in the world.

IntroductionClimate Central’s Surging Seas: Risk Zone map shows areas vulnerable to near-term flooding from different combinations of sea level rise, storm surge, tides, and tsunamis, or to permanent submersion by long-term sea level rise. Within the U.S., it incorporates the latest, high-resolution, high-accuracy lidar elevation data supplied by NOAA (exceptions: see Sources), displays points of interest, and contains layers displaying social vulnerability, population density, and property value. Outside the U.S., it utilizes satellite-based elevation data from NASA in some locations, and Climate Central’s more accurate CoastalDEM in others (see Methods and Qualifiers). It provides the ability to search by location name or postal code.The accompanying Risk Finder is an interactive data toolkit available for some countries that provides local projections and assessments of exposure to sea level rise and coastal flooding tabulated for many sub-national districts, down to cities and postal codes in the U.S. Exposure assessments always include land and population, and in the U.S. extend to over 100 demographic, economic, infrastructure and environmental variables using data drawn mainly from federal sources, including NOAA, USGS, FEMA, DOT, DOE, DOI, EPA, FCC and the Census.This web tool was highlighted at the launch of The White House's Climate Data Initiative in March 2014. Climate Central's original Surging Seas was featured on NBC, CBS, and PBS U.S. national news, the cover of The New York Times, in hundreds of other stories, and in testimony for the U.S. Senate. The Atlantic Cities named it the most important map of 2012. Both the Risk Zone map and the Risk Finder are grounded in peer-reviewed science.Back to topMethods and QualifiersThis map is based on analysis of digital elevation models mosaicked together for near-total coverage of the global coast. Details and sources for U.S. and international data are below. Elevations are transformed so they are expressed relative to local high tide lines (Mean Higher High Water, or MHHW). A simple elevation threshold-based “bathtub method” is then applied to determine areas below different water levels, relative to MHHW. Within the U.S., areas below the selected water level but apparently not connected to the ocean at that level are shown in a stippled green (as opposed to solid blue) on the map. Outside the U.S., due to data quality issues and data limitations, all areas below the selected level are shown as solid blue, unless separated from the ocean by a ridge at least 20 meters (66 feet) above MHHW, in which case they are shown as not affected (no blue).Areas using lidar-based elevation data: U.S. coastal states except AlaskaElevation data used for parts of this map within the U.S. come almost entirely from ~5-meter horizontal resolution digital elevation models curated and distributed by NOAA in its Coastal Lidar collection, derived from high-accuracy laser-rangefinding measurements. The same data are used in NOAA’s Sea Level Rise Viewer. (High-resolution elevation data for Louisiana, southeast Virginia, and limited other areas comes from the U.S. Geological Survey (USGS)). Areas using CoastalDEM™ elevation data: Antigua and Barbuda, Barbados, Corn Island (Nicaragua), Dominica, Dominican Republic, Grenada, Guyana, Haiti, Jamaica, Saint Kitts and Nevis, Saint Lucia, Saint Vincent and the Grenadines, San Blas (Panama), Suriname, The Bahamas, Trinidad and Tobago. CoastalDEM™ is a proprietary high-accuracy bare earth elevation dataset developed especially for low-lying coastal areas by Climate Central. Use our contact form to request more information.Warning for areas using other elevation data (all other areas)Areas of this map not listed above use elevation data on a roughly 90-meter horizontal resolution grid derived from NASA’s Shuttle Radar Topography Mission (SRTM). SRTM provides surface elevations, not bare earth elevations, causing it to commonly overestimate elevations, especially in areas with dense and tall buildings or vegetation. Therefore, the map under-portrays areas that could be submerged at each water level, and exposure is greater than shown (Kulp and Strauss, 2016). However, SRTM includes error in both directions, so some areas showing exposure may not be at risk.SRTM data do not cover latitudes farther north than 60 degrees or farther south than 56 degrees, meaning that sparsely populated parts of Arctic Circle nations are not mapped here, and may show visual artifacts.Areas of this map in Alaska use elevation data on a roughly 60-meter horizontal resolution grid supplied by the U.S. Geological Survey (USGS). This data is referenced to a vertical reference frame from 1929, based on historic sea levels, and with no established conversion to modern reference frames. The data also do not take into account subsequent land uplift and subsidence, widespread in the state. As a consequence, low confidence should be placed in Alaska map portions.Flood control structures (U.S.)Levees, walls, dams or other features may protect some areas, especially at lower elevations. Levees and other flood control structures are included in this map within but not outside of the U.S., due to poor and missing data. Within the U.S., data limitations, such as an incomplete inventory of levees, and a lack of levee height data, still make assessing protection difficult. For this map, levees are assumed high and strong enough for flood protection. However, it is important to note that only 8% of monitored levees in the U.S. are rated in “Acceptable” condition (ASCE). Also note that the map implicitly includes unmapped levees and their heights, if broad enough to be effectively captured directly by the elevation data.For more information on how Surging Seas incorporates levees and elevation data in Louisiana, view our Louisiana levees and DEMs methods PDF. For more information on how Surging Seas incorporates dams in Massachusetts, view the Surging Seas column of the web tools comparison matrix for Massachusetts.ErrorErrors or omissions in elevation or levee data may lead to areas being misclassified. Furthermore, this analysis does not account for future erosion, marsh migration, or construction. As is general best practice, local detail should be verified with a site visit. Sites located in zones below a given water level may or may not be subject to flooding at that level, and sites shown as isolated may or may not be be so. Areas may be connected to water via porous bedrock geology, and also may also be connected via channels, holes, or passages for drainage that the elevation data fails to or cannot pick up. In addition, sea level rise may cause problems even in isolated low zones during rainstorms by inhibiting drainage.ConnectivityAt any water height, there will be isolated, low-lying areas whose elevation falls below the water level, but are protected from coastal flooding by either man-made flood control structures (such as levees), or the natural topography of the surrounding land. In areas using lidar-based elevation data or CoastalDEM (see above), elevation data is accurate enough that non-connected areas can be clearly identified and treated separately in analysis (these areas are colored green on the map). In the U.S., levee data are complete enough to factor levees into determining connectivity as well.However, in other areas, elevation data is much less accurate, and noisy error often produces “speckled” artifacts in the flood maps, commonly in areas that should show complete inundation. Removing non-connected areas in these places could greatly underestimate the potential for flood exposure. For this reason, in these regions, the only areas removed from the map and excluded from analysis are separated from the ocean by a ridge of at least 20 meters (66 feet) above the local high tide line, according to the data, so coastal flooding would almost certainly be impossible (e.g., the Caspian Sea region).Back to topData LayersWater Level | Projections | Legend | Social Vulnerability | Population | Ethnicity | Income | Property | LandmarksWater LevelWater level means feet or meters above the local high tide line (“Mean Higher High Water”) instead of standard elevation. Methods described above explain how each map is generated based on a selected water level. Water can reach different levels in different time frames through combinations of sea level rise, tide and storm surge. Tide gauges shown on the map show related projections (see just below).The highest water levels on this map (10, 20 and 30 meters) provide reference points for possible flood risk from tsunamis, in regions prone to them.

At 282 feet below sea level, Death Valley in the Mojave Desert, California is the lowest point of elevation in the United States (and North America). Coincidentally, Death Valley is less than 85 miles from Mount Whitney, the highest point of elevation in the mainland United States. Death Valley is one of the hottest places on earth, and in 1913 it was the location of the highest naturally occurring temperature ever recorded on Earth (although some meteorologists doubt its legitimacy). New Orleans Louisiana is the only other state where the lowest point of elevation was below sea level. This is in the city of New Orleans, on the Mississippi River Delta. Over half of the city (up to two-thirds) is located below sea level, and recent studies suggest that the city is sinking further - man-made efforts to prevent water damage or flooding are cited as one reason for the city's continued subsidence, as they prevent new sediment from naturally reinforcing the ground upon which the city is built. These factors were one reason why New Orleans was so severely impacted by Hurricane Katrina in 2005 - the hurricane itself was one of the deadliest in history, and it destroyed many of the levee systems in place to prevent flooding, and the elevation exacerbated the damage caused. Highest low points The lowest point in five states is over 1,000 feet above sea level. Colorado's lowest point, at 3,315 feet, is still higher than the highest point in 22 states or territories. For all states whose lowest points are found above sea level, these points are located in rivers, streams, or bodies of water.

United States US: Land Area Where Elevation is Below 5 Meters: % of Total Land Area data was reported at 1.168 % in 2010. This stayed constant from the previous number of 1.168 % for 2000. United States US: Land Area Where Elevation is Below 5 Meters: % of Total Land Area data is updated yearly, averaging 1.168 % from Dec 1990 (Median) to 2010, with 3 observations. The data reached an all-time high of 1.168 % in 2010 and a record low of 1.168 % in 2010. United States US: Land Area Where Elevation is Below 5 Meters: % of Total Land Area data remains active status in CEIC and is reported by World Bank. The data is categorized under Global Database’s USA – Table US.World Bank: Land Use, Protected Areas and National Wealth. Land area below 5m is the percentage of total land where the elevation is 5 meters or less.; ; Center for International Earth Science Information Network (CIESIN)/Columbia University. 2013. Urban-Rural Population and Land Area Estimates Version 2. Palisades, NY: NASA Socioeconomic Data and Applications Center (SEDAC). http://sedac.ciesin.columbia.edu/data/set/lecz-urban-rural-population-land-area-estimates-v2.; Weighted Average;

Land impacted by inundation due to sea level rise is projected to rise in the United States under various Shared Socioeconomic Pathways (SSP). The mean projected land area affected due to sea level rise under the SSP1-2.6 low emission scenario is expected to be more than ***** square kilometers at the end of the century relative to the historic baseline. In comparison, the projected land area affected under the SSP5-8.5 high emission scenario is approximately ****** square kilometers at the same time frame.

The average level of the ocean has been rising since we started measuring and recording this data. According to the National Aeronautics and Space Agency (NASA), since 1900 the global mean sea level has risen more than 200 millimeters (nearly 8 inches) and nearly half of that increase has occurred since 1993 in a concerning change in rate of rise.Sea level rise is one of the many effects of global warming. Scientists attribute sea level rise to two things, melting ice and increased ocean water temperatures. Increasing air temperatures, particularly in the polar regions, has encouraged the melting of land-based ice reserves such as glaciers, ice sheets, and permafrost. Historically, warm season ice melt was balanced by replenishment during the cold season but warming temperatures have created conditions where melting exceeds the buildup of ice. This water flows through rivers and streams to the ocean in quantities sufficient to contribute to sea level rise.Oceans are also massive heat sinks. They pull large quantities of atmospheric heat and greenhouse gases such as carbon dioxide and store it in the ocean. The sea changes temperature much more slowly than the air and over time ocean temperatures have continued to build. As the ocean water warms it expands causing the sea levels to rise.Sea levels are not rising equally across Earth. Some areas are already experiencing significant impacts due to the rising water levels while others have seen minimal changes. This is due to a variety of reasons. First, despite how it is typically illustrated Earth is not perfectly round so the height of the ocean at any given point varies. This can be due to the Earth’s rotation, ocean currents, or prevailing wind speed and direction.Experts consider sea level rise and urgent climatic threat. Many low-lying places such as islands and coastal areas are already experiencing high waters. Higher waters also make storms such as hurricanes more dangerous due to higher storm surges and flooding. As coastlines could lose key infrastructure, land will become uninhabitable, and many people could lose their livelihoods. It is estimated 10 percent of the world’s population could be impacted as the waters rise. Many of the approximately 770 million people could be forced to migrate to higher ground, or in the case of island countries, such as Kiribati, to new countries once theirs sinks below the sea.This map was created with data from the National Oceanic and Atmospheric Administration (NOAA), NASA, and the United States Geological Survey. Experts used an elevation data and the NOAA model Scenarios of Future Mean Seal Level to illustrate the scale of potential coastal flooding. The mapmaker chose to remove levees from the data, so the areas flooded include places, particularly in the states of Texas and Louisiana, that are presently protected by this infrastructure. It is important to note that these are possible outcomes. This model does not include possible erosion, subsidence, or construction that may occur between 2022 when this data was created and 2030, 2050, or 2090 respectively. While models are powerful tools it is difficult to calculate every aspect that shapes our environment.Learn more about how coastal communities are impacted by sea level rise with this StoryMap by NOAA’s Office for Coastal Management, The King Tides Project: Snap the shore, See the Future.

Future mean sea levels for Sweden's coast for the middle of the century (2050) and the end of the century (2100) are calculated for three different climate scenarios. GIS layers for the calculated mean water levels have been developed and show the location of the shoreline on average. The inventories are based on projections from the IPCC Special Report The Ocean and Cryosphere in a Changing Climate (SROCC) that was decided in September 2019. Inventories include the median, upper and lower boundary of the likely range of projected sea level rises under three different emission scenarios: RCP2,6, RCP4,5 and RCP8,5. The likely range is limited by the 17th and 83rd percentiles. Those levels therefore do not constitute either a lower or an upper limit for the possible level of the mean sea level in 2050 and 2100. A total of 252 stocks are available for download.

Please note that newer bases have been developed. You can find it under the metadata entry "Future mean sea level - Based on data from IPCC AR6 WG 1 (2021)", https://www.smhi.se/data/explorer-oppna-data/future-mean-water-stand-based-pa-data-fran-ipcc-ar6-wg-1-2021.

LIMITATIONS The geographical extent is limited to the area between the Swedish territorial boundary in the sea and 1.0 - 1.5 km inside the coastline.

Comments: 1. The map data used in the calculations lacks detailed information on where there are or are missing natural or constructed obstacles or passages between land and sea. This means that land below future sea level may appear to be flooded even though there may be obstacles to flooding from the sea. 2. There are instances where land rise in parts of Sweden is greater than sea level rise. This means that the sea level in the near future will be lower than it is today. In these places, where land rises faster than the sea rises, the future sea level is shown as if it were unchanged, i.e. at the same level as today. 3. Possible effects on the coastline of a change in mean sea level (e.g. erosion) cannot be deduced from the map.

SCOPE All data relates to Sweden. Coordinates for the area are given by the corners southwest 55.25N, 10.79E northeast 65.91N, 24.18E

USE The inventories provide a comprehensive basis for information on future sea levels. The aim is not to provide a complete basis for decision-making, but to give an indication of the areas in which a more detailed basis should be developed. Please note that there are later calculations of future mean water levels than those found in this data material.

Stocks show the shoreline of possible future mean sea levels in the middle of the century (2050) and the end of the century (2100). This is based on information on mean sea level during the reference period (1986-2005), sea level rise including regional variations and local land uplift. In the planning context, consideration should also be given to, among other things, high-water events that may occur, for example, during storms. High-water events are not included in these layers.

FORMAT Shape and WMS

Land impacted by inundation due to sea level rise is projected to rise in France under various Shared Socioeconomic Pathways (SSP). Under the SSP1-*** low emission scenario, the mean amount of land that falls below local mean sea level due to climate change impact on sea level rise in Mexico is projected to reach *** square kilometers at the end of the century relative to the historic baseline.

Land impacted by inundation due to sea level rise is projected to rise in Mexico under various Shared Socioeconomic Pathways (SSP). Under the SSP1-2.6 low emission scenario, the mean amount of land that falls below local mean sea level due to climate change impact on sea level rise in Mexico is projected to reach 3790 square kilometers at the end of the century relative to the historic baseline.

This data release presents an update to the Coastal Response Likelihood (CRL) model (Lentz and others 2015); a spatially explicit, probabilistic model that evaluates coastal response for the Northeastern U.S. under various sea-level scenarios. The model considers the variable nature of the coast and provides outputs at spatial and temporal scales suitable for decision support. Updated model results provide higher spatial resolution predictions (from 30 meters (m) to 10 m) of adjusted land elevation ranges (AE) with respect to projected relative sea-level scenarios, a likelihood estimate of this outcome (PAE), and a probability of coastal response (CR) characterized as either static (inundated) or dynamic (maintaining or changing state). The predictions span the coastal zone vertically from 10 m below to 10 m above mean high water (MHW). Results are produced at a horizontal resolution of 10 meters for four decades (2030, 2050, 2080 and 2100) and two possible sea-level change scenarios (Intermediate Low (IL), Intermediate High (IH)) as defined by Sweet and others 2022. Adjusted elevations and their respective probabilities are generated using regional geospatial datasets of relative sea-level scenarios and current elevation data. Coastal response outcomes are determined by combining adjusted elevation outputs with land cover data and expert judgment (Lentz and others 2015) to assess whether an area is likely to maintain its existing land class, or transition to a new one (dynamic), or become submerged (static). The intended users of these data include scientific researchers, coastal planners, and natural resource managers.

[This is an archived copy of a dataset originally hosted at https://www.coast.noaa.gov/slr/ and https://coast.noaa.gov/slrdata/. Dataset captured July 2025 by UCSB Library Research Data Services.] These data were created as part of the National Oceanic and Atmospheric Administration Office for Coastal Management's efforts to create an online mapping viewer depicting potential sea level rise and its associated impacts on the nation's coastal areas. The purpose of the mapping viewer is to provide coastal managers and scientists with a preliminary look at sea level rise (slr) and coastal flooding impacts. The viewer is a screening-level tool that uses nationally consistent data sets and analyses. Data and maps provided can be used at several scales to help gauge trends and prioritize actions for different scenarios. The Sea Level Rise and Coastal Flooding Impacts Viewer may be accessed at: https://www.coast.noaa.gov/slr

These data depict the potential inundation of coastal areas resulting from a projected 0.5 to 10 feet rise in sea level above current Mean Higher High Water (MHHW) conditions in half foot increments. The process used to produce the data can be described as a modified bathtub approach that attempts to account for both local/regional tidal variability as well as hydrological connectivity. The process uses two source datasets to derive the final inundation rasters and polygons and accompanying low-lying polygons for each iteration of sea level rise: the Digital Elevation Model (DEM) of the area and a tidal surface model that represents spatial tidal variability. The tidal model is created using the NOAA National Geodetic Survey's VDATUM datum transformation software (http://vdatum.noaa.gov) in conjunction with spatial interpolation/extrapolation methods and represents the MHHW tidal datum in orthometric values (North American Vertical Datum of 1988).

The model used to produce these data does not account for erosion, subsidence, or any future changes in an area's hydrodynamics. It is simply a method to derive data in order to visualize the potential scale, not exact location, of inundation from sea level rise.

Both raster and vector data are provided for each sea level rise amount above MHHW. The raster data represent both the horizontal extent of inundation and depth above ground, in meters. The vector data represent the horizontal extent of both hydrologically connected and unconnected inundation. The vector "slr" data represent inundation that is hydrologically connected to the ocean. The vector "low" data represent areas that are hydrologically unconnected to the ocean, but are below the sea level rise amount and may also flood.

For more information, contact coastal.info@noaa.gov.

In a Climate Change (CC) context, low-lying areas like marshes are more vulnerable to Sea Level Rise (SLR) or extreme climate events leading to coastal flooding. The main objective of this study is to help local stakeholders determine the best coastal management strategy for the Moëze marsh (France) that can contribute to adapt to SLR in this zone. To do so, we used the MARS hydrodynamic model to simulate coastal overflowing in the zone for different scenarios. We first calibrated the model based on data from the Xynthia storm which occurred on February 28th 2010. Our focus is on modeling the high astronomical tide-induced flooding, taking into account regional SLR projections by 2030 and 2050 under the pessimistic RCP 8.5 CC scenario. Several Coastal management configurations proposed by local decision-makers, as well as different land-use projections were considered. The results highlight that the implementation of closed defenses around human and economic stakes do not lead to significant reductions in flooding (surface extent and maximum water height) compared to the case where the sea-dikes are no longer maintained and the coastline is unconstrained. This can be explained by the fact that these stake zones were historically built on higher points of the marsh. We have also shown that land-use changes have an influence on flooding in the Moëze marsh, especially an increase greater than 0.25 m in the maximum simulated height when considering a new land-use by 2030. The increase is less pronounced (under 0.25 m) when considering a new land-use by 2050. These results do not take into account the possible future evolution of the topography due, for example, to the presence of new habitats that would trap the sediments.

Tidal habitats host a diversity of species and provide hydrological services such as shoreline protection and nutrient attenuation. Accretion of sediment and biomass enables tidal marshes and swamps to grow vertically, providing a degree of resilience to rising sea levels. Even if accelerating sea level rise overcomes this vertical resilience, tidal habitats have the potential to migrate inland as they continue to occupy land that falls within the new tide range elevations. The existence of developed land inland of tidal habitats, however, may prevent this migration as efforts are often made to dyke and protect developments. To test the importance of inland migration to maintaining tidal habitat abundance under a range of potential rates of sea level rise, we developed a spatially explicit elevation tracking and habitat switching model, dubbed the Marsh Accretion and Inundation Model (MAIM), which incorporates elevation-dependent net land surface elevation gain functions. We applied the model to the metropolitan Washington, DC region, finding that the abundance of small National Park Service units and other public open space along the tidal Potomac River system provides a refuge to which tidal habitats may retreat to maintain total habitat area even under moderate sea level rise scenarios (0.7 m and 1.1 m rise by 2100). Under a severe sea level rise scenario associated with ice sheet collapse (1.7 m by 2100) habitat area is maintained only if no development is protected from rising water. If all existing development is protected, then 5%, 10%, and 40% of the total tidal habitat area is lost by 2100 for the three sea level rise scenarios tested.

The United States has an average elevation of roughly 2,500 feet (763m) above sea level, however there is a stark contrast in elevations across the country. Highest states Colorado is the highest state in the United States, with an average elevation of 6,800 feet (2,074m) above sea level. The 10 states with the highest average elevation are all in the western region of the country, as this is, by far, the most mountainous region in the country. The largest mountain ranges in the contiguous western states are the Rocky Mountains, Sierra Nevada, and Cascade Range, while the Appalachian Mountains is the longest range in the east - however, the highest point in the U.S. is Denali (Mount McKinley), found in Alaska. Lowest states At just 60 feet above sea level, Delaware is the state with the lowest elevation. Delaware is the second smallest state, behind Rhode Island, and is located on the east coast. Larger states with relatively low elevations are found in the southern region of the country - both Florida and Louisiana have an average elevation of just 100 feet (31m) above sea level, and large sections of these states are extremely vulnerable to flooding and rising sea levels, as well as intermittent tropical storms.

Land impacted by inundation due to sea level rise is projected to fluctuate over the years in the Netherlands under various Shared Socioeconomic Pathways (SSP). Under the SSP1-2.6 low emission scenario, the mean projected area affected by sea level rise in the Netherlands is just over 6892 square kilometers in the next decade relative to the historic baseline. This figure decreases at the end of the century with an area of, 4729 square kilometers affected. This represents a decrease of more than ** percent in land impacted by inundation during these time frames.

Digital elevation model cover: areas located between 10 meters below and above sea level. ETOPO5 was generated from a digital data base of land and sea- floor elevations on a 5-minute latitude/longitude grid.

Areas projected to be between high tide and mean low tide with 5 feet of sea level rise. It also includes areas projected to be submerged with 5 feet of sea level rise. Kept all areas impacted by sea level rise (both subtidal and intertidal) to display on the web map.

Purpose:The coastal inundation hazard layers map describes the areas exposed to extreme water levels caused by storm tides, wave setup and sea-level rise under the following scenarios (where AEP is the Annual Exceedance Probability or the chance of occurring each year, ARI is the Average Recurrence Interval):20% AEP (5 year return)5% AEP (20 year return)2% AEP (50 year return)1% AEP (100 year return): to demonstrate present day risk in alignment with the Auckland Unitary Plan activity controls2% AEP (50 year return) + 1m sea level rise2% AEP (50 year return) + 2m sea level rise1% AEP (100 year return) + 1m sea level rise: in alignment with Auckland Unitary Plan activity controls1% AEP (100 year return) + 2m sea level rise: to demonstrate longer term risk with ongoing sea-level riseThis is a generalised version of the data. Download the original full dataset with layer files here:https://data-aucklandcouncil.opendata.arcgis.com/datasets/coastal-inundation-hazards-geodatabase/aboutThe layer takes into account extreme sea levels calculated between 2013 and 2019, as compiled in Carpenter, N., R Roberts and P Klinac (2020). Auckland’s exposure to coastal inundation by storm-tides and waves. Auckland Council technical report, TR2020/24. Auckland’s exposure to coastal inundation by storm-tides and waves (knowledgeauckland.org.nz)Sea-level rise values applied currently align with the projections by the Intergovernmental Panel on Climate Change sixth assessment report (2021), and the Ministry for the Environment (2022) Interim guidance on the use of new sea-level rise projections, which updates the Ministry for the Environment Coastal Hazards and Climate Change Guidance for Local Government (2017). In MfE’s (2022) Interim guidance, (excluding vertical land movement) one metre sea-level rise is projected to occur between 2095 - >2200, depending on the emission scenario used. Two metre sea-level rise is projected to occur in the longer term (beyond 2150). MfE’s (2022) Interim guidance recommends the inclusion of vertical land movement (VLM) in relative sea level rise considerations. These are not included in the above sea level rise predictions due to the high VLM variability across the region. Vertical land movement is generally predicted to increase the rates of relative sea level rise for the Auckland region so should also be incorporated in planning and design.Refer to Interim guidance on the use of new sea-level rise projections | Ministry for the Environment for more information on MfE’s interim guidance on sea level rise and vertical land movement.Lineage:3Extreme sea levels for the Auckland region were derived by NIWA in 2013 (Part 1 of Technical Report 2020/24). From 2016-2019, additional extreme sea level data was gathered for:The east coast estuaries (NIWA, 2016; Part 2 of Technical Report 2020/24)Parakai/Helensville Harbour (DHI, 2019; Part 3 of Technical Report 2020/24)Great Barrier Island (NIWA, 2019; Part 4 of Technical Report 2020/24)In 2020, these levels were projected onto the land topography (derived from the 2016-2018 LiDAR survey) by Stantec to establish the extent of coastal flooding. Creation Date: 15/12/2020Update Cycle: Adhoc – when improved data becomes availableThis data is available to the public on the Geomaps viewer and is copied into LIMsContact Person: Natasha CarpenterContact Position:Coastal Management Practice Lead, Infrastructure and Environmental ServicesCouncil Contact:Natasha.Carpenter@aucklandcouncil.govt.nzConstraints – General:The Coastal Inundation data is subject to updates to reflect the latest, best available understanding of storm tides, waves and sea-level rise processes.The geodatabase contains a copy of the historic inundation mapping, which is superseded by the publication of the 2020 data. The superseded data is identified by having a validation state of 0, whereas the published data has a validation state of 3 (valid and public).Constraints – Legal: This data is available to the public on the Geomaps viewer and is copied into LIMsConstraints – Security: The Coastal Inundation data is available to the public Under Creative Commons license.

Sea-level rise (SLR) through the twenty-first century and beyond is inevitable, threatening coastal areas and their inhabitants unless there is appropriate adaptation. We investigate coastal flooding to 2100 under the full range of IPCC AR6 (2021) SLR scenarios, assuming plausible adaptation. The adaptation selects the most economically robust adaptation option: protection or retreat. People living in unprotected coastal areas that are frequently inundated (below 1-in-1-year flood level) are assumed to migrate, and the land is considered lost. Globally, across the range of SLR and related socioeconomic scenarios, we estimate between 4 million and 72 million people could migrate over the twenty-first century, with a net land loss ranging from 2,800 to 490,000 km2. India and Vietnam consistently show the highest absolute migration, while Small Island Developing States are the most affected when considering relative migration and land loss. Protection is the most robust adaptation option under all scenarios for 2.8% of the global coastline, but this safeguards 78% of the global population and 91% of assets in coastal areas. Climate stabilisation (SSP1–1.9 and SSP1–2.6) does not avoid all coastal impacts and costs as sea levels still rise albeit more slowly. The impacts and costs are also sensitive to the socioeconomic scenario: SSP3–7.0 experiences higher migration than SSP5–8.5 despite lower SLR, reflecting a larger population and lower GDP. Our findings can inform national and intergovernmental agencies and organisations on the magnitude of SLR impacts and costs and guide assessments of adaptation policies and strategies.

Purpose:The coastal inundation hazard layers map describes the areas exposed to extreme water levels caused by storm tides, wave setup and sea-level rise under the following scenarios (where AEP is the Annual Exceedance Probability or the chance of occurring each year, ARI is the Average Recurrence Interval):20% AEP (5 year return)5% AEP (20 year return)2% AEP (50 year return)1% AEP (100 year return): to demonstrate present day risk in alignment with the Auckland Unitary Plan activity controls2% AEP (50 year return) + 1m sea level rise2% AEP (50 year return) + 2m sea level rise1% AEP (100 year return) + 1m sea level rise: in alignment with Auckland Unitary Plan activity controls1% AEP (100 year return) + 2m sea level rise: to demonstrate longer term risk with ongoing sea-level riseThis is a generalised version of the data. Download the original full dataset with layer files here:https://data-aucklandcouncil.opendata.arcgis.com/datasets/coastal-inundation-hazards-geodatabase/aboutThe layer takes into account extreme sea levels calculated between 2013 and 2019, as compiled in Carpenter, N., R Roberts and P Klinac (2020). Auckland’s exposure to coastal inundation by storm-tides and waves. Auckland Council technical report, TR2020/24. Auckland’s exposure to coastal inundation by storm-tides and waves (knowledgeauckland.org.nz)Sea-level rise values applied currently align with the projections by the Intergovernmental Panel on Climate Change sixth assessment report (2021), and the Ministry for the Environment (2022) Interim guidance on the use of new sea-level rise projections, which updates the Ministry for the Environment Coastal Hazards and Climate Change Guidance for Local Government (2017). In MfE’s (2022) Interim guidance, (excluding vertical land movement) one metre sea-level rise is projected to occur between 2095 - >2200, depending on the emission scenario used. Two metre sea-level rise is projected to occur in the longer term (beyond 2150). MfE’s (2022) Interim guidance recommends the inclusion of vertical land movement (VLM) in relative sea level rise considerations. These are not included in the above sea level rise predictions due to the high VLM variability across the region. Vertical land movement is generally predicted to increase the rates of relative sea level rise for the Auckland region so should also be incorporated in planning and design.Refer to Interim guidance on the use of new sea-level rise projections | Ministry for the Environment for more information on MfE’s interim guidance on sea level rise and vertical land movement.Lineage:3Extreme sea levels for the Auckland region were derived by NIWA in 2013 (Part 1 of Technical Report 2020/24). From 2016-2019, additional extreme sea level data was gathered for:The east coast estuaries (NIWA, 2016; Part 2 of Technical Report 2020/24)Parakai/Helensville Harbour (DHI, 2019; Part 3 of Technical Report 2020/24)Great Barrier Island (NIWA, 2019; Part 4 of Technical Report 2020/24)In 2020, these levels were projected onto the land topography (derived from the 2016-2018 LiDAR survey) by Stantec to establish the extent of coastal flooding. Creation Date: 15/12/2020Update Cycle: Adhoc – when improved data becomes availableThis data is available to the public on the Geomaps viewer and is copied into LIMsContact Person: Natasha CarpenterContact Position:Coastal Management Practice Lead, Infrastructure and Environmental ServicesCouncil Contact:Natasha.Carpenter@aucklandcouncil.govt.nzConstraints – General:The Coastal Inundation data is subject to updates to reflect the latest, best available understanding of storm tides, waves and sea-level rise processes.The geodatabase contains a copy of the historic inundation mapping, which is superseded by the publication of the 2020 data. The superseded data is identified by having a validation state of 0, whereas the published data has a validation state of 3 (valid and public).Constraints – Legal: This data is available to the public on the Geomaps viewer and is copied into LIMsConstraints – Security: The Coastal Inundation data is available to the public Under Creative Commons license.