High accuracy coastal flood mapping for Norway using LiDAR data - Revised figures Kristian Breili1,2, Matthew James Ross Simpson1, Erlend Klokkervold3, and Oda Roaldsdotter Ravndal4 1Geodetic Institute, Norwegian Mapping Authority, 3507 Hønefoss, Norway 2Faculty of Science and Technology, Norwegian University of Life Sciences, 1432 Ås, Norway 3Geographic Information System Development, Norwegian Mapping Authority, 3507 Hønefoss, Norway 4Hydrographic Service, Norwegian Mapping Authority, 4021 Stavanger, Norway Correspondence: Kristian Breili ([email protected])
1 Figure 1. Red lines indicate areas covered by the inundation maps per December 2018. Information for all water levels is not available for all mapped zones due to a lack of knowledge on ocean tides for parts of the coast. In these zones, only the storm-surge return heights can be calculated because they are not referenced to MHW. The green markers indicate locations discussed in the text.
2 Figure 2. Stack of inundation maps covering the village Lærdalsøyri located on a glaciofluvial delta at the head of Sognefjorden. Violet: Present MHW. Green: MHW for 2090 (0.58 m above present MHW). Orange: Present 200-year storm surge (1.00 m above present MHW). Red: 200-year storm surge for 2090 (1.58 m above present MHW). Inset: Photo of the village Lærdalsøyri (Photo: Magnhild Aspevik)
3 Figure 3. Stack of inundation maps covering Randaberg located on soft moraine in the southwest of Norway. Violet: Present MHW. Green: MHW for 2090 (0.79 m above present MHW). Orange: present 200-year storm surge (0.99 m above present MHW). Red: 200-year storm surge for 2090 (1.78 m above present MHW). Inset: Soft sand dunes at Sandestranda close to Randaberg. Photo: Oda R. Ravndal.
200000 24% Developed Public 13% 3500 Public 39% 1000 Nature Private industry Private Public facility Private 3000 Primary industry 160000 Critical infrastructure 800 27% 30% 2500 34% 47%
] 120000 2 51%
m 600 2000 k [
60% a e
r 134% A 80000 Roads [km] 1500 162% 400
Number of buildings 52% 1000 235% 40000 200 500
0 0 0 MHW MHW MHW 20-yr 20-yr 20-yr 200-yr 200-yr 200-yr 1000-yr 1000-yr 1000-yr 1000-yr+1m 1000-yr+1m 1000-yr+1m
Figure 4. The bars indicate the size of areas (left), the number of buildings (middle), and the length of roads (right) affected by sea-level rise and storm surge in Norway. For each water level, the left and right bars indicate affected objects at present and for 2090, respectively. Percentages on top of right bars indicate total’s change from now to 2090 due to sea-level rise.
4 Figure 5. Affected land areas due to a 200 year storm-surge hazard at present (left figures) and for 2090 (right figures). The radius of the bubbles is for each municipality proportional to the size of flooded land area (upper figures) and flooded land areas as percentage of the municipality’s total area (lower figures).
5 Figure 6. Affected buildings due to a 200 year storm-surge hazard at present (left) and for 2090 (right). The radius of the bubbles are proportional to the number of exposed buildings.
Figure 7. Affected roads due to a 200 year storm-surge hazard at present (left) and for 2090 (right). The radius of the bubbles are proportional to the length of exposed roads.
6 Vikna Sandøy
Smøla Kvitsøy
Fredrikstad Værøy
Vestvågøy Ørland
Vågan Hvaler
Frøya Vikna
Brønnøy Færder
Nærøy Giske
Lødingen Developed Leka Developed Nature Nature Bodø Public facility Smøla Public facility Primary industry Primary industry
0 5 10 15 20 25 30 0 5 10 15 20 25 Area [km2] Percentage of total area
Bergen Fredrikstad
Fjell Færder
Bømlo Sandefjord
Karmøy Hvaler
Tromsø Vestvågøy
Arendal Vikna
Kragerø Vågan
Lindås Arendal
Askøy Public Brønnøy Private industry Kvinnherad Private Bjugn Public Critical infrastructure Private
0 1000 2000 3000 4500 0 10 20 30 40 45 Buildings Roads [km]
Figure 8. The ten municipalities with most land-areas, buildings, and roads affected by a 200-year storm-surge hazard at present sea level.
7 Vikna 32.6% Kvitsøy
Smøla 49.4% Sandøy
Vestvågøy 51.5% Ørland
Vågan 55.7% Værøy
Fredrikstad 28.7% Giske
Frøya 46.1% Hvaler
Brønnøy 36.8% Vikna
Nærøy 39.6% Færder
Tromsø 48.3% Developed Smøla Developed Nature Nature Hitra 51.4% Public facility Fedje Public facility Primary industry Primary industry
0 5 10 15 20 25 30 0 5 10 15 20 25 Area [km2] Percentage of total area
Bergen 25.2% Fredrikstad 73.6%
Karmøy 34.4% Vågan 217.1%
Bømlo 19.7% Vestvågøy 182.7%
Fjell 7.7% Mandal 484.1%
Tromsø 30.2% Færder 73.1%
Arendal 34.3% Arendal 112.2%
Kragerø 27.2% Sandefjord 61.4%
Kristiansand 45.4% Tromsø 185.2%
Vindafjord 53.8% Public Hvaler 56.4% Private industry Kvinnherad 24.4% Private Stavanger 256.8% Public Critical infrastructure Private
0 1000 2000 3000 4500 0 10 20 30 40 45 Buildings Roads [km]
Figure 9. Similar as Figure 8, but for 2090. The percentages indicate total’s change from now to 2090 due to sea-level rise.
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