2023-05-08 フィンランド・アールト大学
◆予測は、異なる排出シナリオに基づいて計算され、フィンランドの南部海岸では洪水リスクが増加する一方、北部のバルト海沿岸では海面上昇は予測されていない。ただし、今後数世紀にわたり、グリーンランドや南極の氷河や氷床の融解によって、海面が数メートル上昇する可能性があるため、高リスクのアプリケーションを考慮してより高い海面上昇の可能性も含めて予測が算出された。
＜関連情報＞
- https://www.aalto.fi/en/news/land-uplift-protects-the-finnish-coast-from-rising-sea-levels-but-not-endlessly
- https://nhess.copernicus.org/articles/23/1613/2023/
フィンランドにおける海面上昇の確率的予測および過去の傾向について Probabilistic projections and past trends of sea level rise in Finland
Havu Pellikka, Milla M. Johansson, Maaria Nordman and Kimmo Ruosteenoja
Natural Hazards and Earth System Sciences Published:28 Apr 2023
DOI:https://doi.org/10.5194/nhess-23-1613-2023
Abstract
We explore past trends and future projections of mean sea level (MSL) at the Finnish coast, in the northeastern Baltic Sea, during the period 1901–2100. We decompose the relative MSL change into three components: regional sea level rise (SLR), postglacial land uplift, and the effect of changes in wind climate. Past trends of regional SLR can be calculated after subtracting the other two components from the MSL trends observed by tide gauges, as the land uplift rates obtained from the semi-empirical model NKG2016LU are independent of tide gauge observations. According to the results, local absolute SLR trends are close to global mean rates. To construct future projections, we combine an ensemble of global SLR projections in a probabilistic framework. In addition, we use climate model results to estimate future changes in wind climate and their effect on MSL in the semi-enclosed Baltic Sea. This yields probability distributions of MSL change for three scenarios representing different future emission pathways. Spatial variations in the MSL projections result primarily from different local land uplift rates: under the medium-emission scenario RCP4.5/SSP2-4.5, for example, the projected MSL change (5 % to 95 % range) over the 21st century varies from −28 (−54 to 24) cm in the Bothnian Bay to 31 (5 to 83) cm in the eastern Gulf of Finland.
