Des collectivités situées le long de la côte du Pacifique des États-Unis tentent de lutter contre l'élévation du niveau de la mer en installant des structures de rivage en roche riprap techniques.
5280 x 3956 px | 44,7 x 33,5 cm | 17,6 x 13,2 inches | 300dpi
Date de la prise de vue:
24 novembre 2022
Lieu:
Salishan, Glen Eden Beach, Oregon
Informations supplémentaires:
Globally, sea levels are rising due to human-caused climate change. Between 1901 and 2018, the globally averaged sea level rose by 15–25 cm (6–10 in), or 1–2 mm per year on average.This rate is accelerating, with sea levels now rising by 3.7 mm per year. Climate scientists expect further acceleration during the 21st century.Climate change heats (and therefore expands) the ocean and melts land-based ice sheets and glaciers.Between 1993 and 2018, the thermal expansion of water contributed 42% to sea level rise; melting of temperate glaciers, 21%; Greenland, 15%; and Antarctica, 8%.: 1576 Over the next 2000 years, the sea level is predicted to rise by 2–3 m (7–10 ft) if global warming is limited to 1.5 °C, by 2–6 m (7–20 ft) if it peaks at 2 °C and by 19–22 metres (62–72 ft) if it peaks at 5 °C.: 21 Sea level rise has a substantial lag in its response to Earth temperature changes. This means that it is virtually certain to continue for a long time, and that its extent in the short term (i.e. around 2050) is insensitive to temperature changes between now and then. Thus, there's confidence that 2050 levels of sea level rise combined with the 2010 population distribution (i.e. absent the effects of population growth and human migration) would result in ~150 million people under the water line during high tide and ~300 million in places which are flooded every year – an increase of 40 and 50 million people relative to 2010 values for the same. At the same time, the impact on temperature from changes in greenhouse gas emissions over the longer term would greatly influence longer-term sea level rise: by 2100, the spread between the lowest and the highest plausible emission trajectories would result in the sea level rise of 0.38–0.77 m (1 ft 3 in – 2 ft 6 in) when using the best-understood median estimates.
