Data
People living on land below the yearly coastal flood level: estimated at today's sea level, projected for 2050 and 2100, world (Kulp & Strauss 2019)
Estimated number of people, in millions, living on land below the local once-a-year coastal flood level (the high-tide line plus the local 1-year flood height), at today's sea level and with the sea levels projected for 2050 and 2100 under low (RCP2.6), moderate (RCP4.5) and high (RCP8.5) emissions, from Supplementary Data 1 of Kulp & Strauss (2019), using the CoastalDEM elevation model. Projected values give the median and the 5th to 95th percentile range of the sea-level projections. Two projection sets are published side by side, never mixed: K14 (Kopp et al. 2014), which the paper calls probabilistic and closely aligned with IPCC findings and which gives the abstract's lead figure (below high tide by 2100 under low emissions); and K17 (Kopp et al. 2017), which adds unstable Antarctic ice, is not probabilistic, and gives the abstract's high-end figures. Both predate the IPCC's Sixth Assessment Report. The population is held at its 2010 distribution (LandScan 2010), so future values show where today's people live relative to future seas, not projected populations. The method is a bathtub model that ignores sea walls and other defences, so it measures exposure, not flooding.
Latest value
250million people
World: land between 56° south and 60° north, where CoastalDEM is defined, home to 99.7% of the world's population in 2010, 2010. Version Nature Communications 10: 4844 (2019), corrected 12 December 2019.
People living on land below the yearly coastal flood level: estimated at today's sea level, projected for 2050 and 2100, world (Kulp & Strauss 2019) (million people)
Show as a table
| Period | Sea level: today's, or projected under an emissions scenario | Sea-level projection | Value (million people) | Range | Status |
|---|---|---|---|---|---|
| 2010 | Today's sea level (that of 2000) | None: today's sea level | 250 | final | |
| 2050 | RCP2.6 (low emissions) | K14 (Kopp et al. 2014): probabilistic, closely aligned with IPCC findings | 300 | 270 to 320 | projection |
| 2100 | RCP2.6 (low emissions) | K14 (Kopp et al. 2014): probabilistic, closely aligned with IPCC findings | 340 | 300 to 400 | projection |
| 2050 | RCP4.5 (moderate emissions) | K14 (Kopp et al. 2014): probabilistic, closely aligned with IPCC findings | 300 | 280 to 320 | projection |
| 2100 | RCP4.5 (moderate emissions) | K14 (Kopp et al. 2014): probabilistic, closely aligned with IPCC findings | 360 | 310 to 420 | projection |
| 2050 | RCP8.5 (high emissions) | K14 (Kopp et al. 2014): probabilistic, closely aligned with IPCC findings | 300 | 280 to 330 | projection |
| 2100 | RCP8.5 (high emissions) | K14 (Kopp et al. 2014): probabilistic, closely aligned with IPCC findings | 390 | 330 to 460 | projection |
| 2050 | RCP2.6 (low emissions) | K17 (Kopp et al. 2017): unstable Antarctic ice, not probabilistic | 290 | 260 to 330 | projection |
| 2100 | RCP2.6 (low emissions) | K17 (Kopp et al. 2017): unstable Antarctic ice, not probabilistic | 350 | 280 to 430 | projection |
| 2050 | RCP4.5 (moderate emissions) | K17 (Kopp et al. 2017): unstable Antarctic ice, not probabilistic | 300 | 260 to 330 | projection |
| 2100 | RCP4.5 (moderate emissions) | K17 (Kopp et al. 2017): unstable Antarctic ice, not probabilistic | 400 | 320 to 510 | projection |
| 2050 | RCP8.5 (high emissions) | K17 (Kopp et al. 2017): unstable Antarctic ice, not probabilistic | 300 | 270 to 340 | projection |
| 2100 | RCP8.5 (high emissions) | K17 (Kopp et al. 2017): unstable Antarctic ice, not probabilistic | 480 | 380 to 630 | projection |
Where it comes from
- Producer
- Scott A. Kulp and Benjamin H. Strauss (Climate Central); published in Nature Communications (Springer Nature) · People on land exposed to sea-level rise and coastal flooding (Kulp & Strauss 2019)
- Version
- Nature Communications 10: 4844 (2019), corrected 12 December 2019
- Fetched
- 2026-10-12 (automatically), 253,535 bytes
- Fingerprint
- sha256 37a6ab2fc25ec632f8dc7485346d0389d953754b591d6b015c45b5d6de4c0b81ETag "8bda3a8ece191add7cff689b5d2893be" · Last-Modified Mon, 04 Dec 2023 17:29:34 GMT
- Cite the producer
- Kulp, S.A., Strauss, B.H. New elevation data triple estimates of global vulnerability to sea-level rise and coastal flooding. Nat Commun 10, 4844 (2019). https://doi.org/10.1038/s41467-019-12808-z
- Producer
- Scott A. Kulp and Benjamin H. Strauss (Climate Central); published in Nature Communications (Springer Nature) · People on land exposed to sea-level rise and coastal flooding (Kulp & Strauss 2019)
- Version
- Nature Communications 10: 4844 (2019), corrected 12 December 2019
- Fetched
- 2026-10-12 (automatically), 65,044 bytes
- Fingerprint
- sha256 2b98673da602184f06aa3d86a939ea6b977dfb847181cf979472349695a1a771ETag "1c83dd29e8d99b1d5ff6a6c73406ac0b" · Last-Modified Mon, 04 Dec 2023 17:29:34 GMT
- Cite the producer
- Kulp, S.A., Strauss, B.H. New elevation data triple estimates of global vulnerability to sea-level rise and coastal flooding. Nat Commun 10, 4844 (2019). https://doi.org/10.1038/s41467-019-12808-z
- Producer
- Scott A. Kulp and Benjamin H. Strauss (Climate Central); published in Nature Communications (Springer Nature) · People on land exposed to sea-level rise and coastal flooding (Kulp & Strauss 2019)
- Version
- Nature Communications 10: 4844 (2019), corrected 12 December 2019
- Fetched
- 2026-10-12 (automatically), 3,903,782 bytes
- Fingerprint
- sha256 912692e7c7a388dfb735f5ec9b1dca5bd6d42b40ed11c88014594ba6b0dd6d3fETag "1745469cbb491e63418a5c0bd7b7bac7" · Last-Modified Mon, 04 Dec 2023 17:29:36 GMT
- Copies
- No Wayback copy recorded yet.Our copy of the exact file
- Cite the producer
- Kulp, S.A., Strauss, B.H. New elevation data triple estimates of global vulnerability to sea-level rise and coastal flooding. Nat Commun 10, 4844 (2019). https://doi.org/10.1038/s41467-019-12808-z
What was done to it
Read Supplementary Data 1 (sha256 37a6ab2fc25e…): its 27 column headings had to be exactly as expected. Kept the 13 rows of Place 'World' (present day, then K14 and K17 under RCP2.6, 4.5 and 8.5 for 2050 and 2100), whose Total is 6800 million people, and from each only the three CoastalDEM columns of RL1: land below the future local high tide line plus the local 1-year coastal flood level. The SRTM, JAXA and MERITDEM columns and the SIDS and country rows are not used here (the country rows are published, in people, by the indicators ending '-by-country').
Code: pipeline/src/envdash/transforms/impacts/kulp_strauss.py · code sha256 5ddd6351a3e35c38… · inputs 37a6ab2fc25e… 2b98673da602… 912692e7c7a3…
Published the 50th percentile as the value and the 5th and 95th percentiles as the lower and upper ends of a 90% interval, exactly as printed in millions of people (nothing rounded or recalculated). The present-day row prints '--' for both percentiles, so it has no range.
Code: pipeline/src/envdash/transforms/impacts/kulp_strauss.py · code sha256 5ddd6351a3e35c38… · inputs 37a6ab2fc25e… 2b98673da602… 912692e7c7a3…
Dated the present-day row 2010, the year of the LandScan population that every row counts (its sea level is that of 2000, the zero of both projection sets), and the projected rows 2050 and 2100, the years of their sea levels; the population stays as it was in 2010.
Code: pipeline/src/envdash/transforms/impacts/kulp_strauss.py · code sha256 5ddd6351a3e35c38… · inputs 37a6ab2fc25e… 2b98673da602… 912692e7c7a3…
Published both projection sets as values of the 'projection' dimension, side by side and never mixed, because the abstract uses both: its 190 M (150–250 M) below high tide by 2100 under low emissions is K14 (K17 gives another range), and its 'up to 630 M' and 'up to 340 M' below the annual flood level by 2100 and mid-century are K17's 95th percentiles under RCP8.5. Checked both, and the present day's 110 M and 250 M, against these cells.
Code: pipeline/src/envdash/transforms/impacts/kulp_strauss.py · code sha256 5ddd6351a3e35c38… · inputs 37a6ab2fc25e… 2b98673da602… 912692e7c7a3…
Checked the file against Table 1 of the corrected article (sha256 912692e7c7a3…, page 3): each of its 24 CoastalDEM totals, median and 90% interval, equals the file's three numbers. Found the 20 sentences that the scope and the cross-checks rely on, each on its page of the article (which page 1 marks 'Corrected: Author correction'), and the 2 on units, exposures and percentiles in the description of the supplementary files (sha256 2b98673da602…).
Code: pipeline/src/envdash/transforms/impacts/kulp_strauss.py · code sha256 5ddd6351a3e35c38… · inputs 37a6ab2fc25e… 2b98673da602… 912692e7c7a3…
What it covers
- Geography
- World: land between 56° south and 60° north, where CoastalDEM is defined, home to 99.7% of the world's population in 2010
- Basis
- Below the local mean higher-high water line plus the local once-a-year coastal flood height (Global Tides and Surge Reanalysis), after the given sea-level rise. People are counted where they lived in 2010 (LandScan 2010); population growth and migration are not modelled. Land cut off from the sea is left out. Present day is the sea level of 2000, the zero of both projection sets. 2050 and 2100 add the median and the 5th to 95th percentiles of the sea-level rise projected by Kopp et al. 2014 (K14) or Kopp et al. 2017 (K17, unstable Antarctic ice) under RCP2.6, 4.5 and 8.5, projections made before the IPCC's Sixth Assessment Report. A bathtub model: sea walls, levees and other defences are not counted (levee locations are not available globally), so protected coasts such as the Netherlands are included. It measures exposure, not flooding.
- Unit
- million people (million people)