Climate Change in Coastal Alaska

Sea Level Rise and Storm Surge

What It Means to Alaskans and How We Can Adapt

What is sea level rise and storm surge?

storm surge at Kivalina

Storm waves batter Kivalina, a remote village on a barrier island along Alaska’s northwest Arctic coast. Photo courtesy Alaska Department of Environmental Conservation.

A warmer global climate is causing glaciers and continental ice sheets to melt, sending increased volumes of freshwater into the sea. At the same time higher temperatures cause thermal expansion of the ocean itself. The result is that sea level is slowly rising.

Why does it matter?

Along the southern shores of Alaska the effect so far is hardly noticeable, because most of the coastline also is slowly rising due to tectonic forces and isostatic rebound (springing back of land after the last ice age). On the Bering Sea coast and in the Arctic, however, communities are experiencing increased damage from storm surges (extreme high water events caused by high winds and low atmospheric pressure), shoreline loss to fierce winter storms, and saltwater intrusion into freshwater sources, sanitation lagoons, and fish and wildlife habitats. Indications are that all of this is being made worse by a gradual rise in sea level.

Furthermore, changing climate may cause a change in storm pathways, bringing more frequent or intense storms to some parts of Alaska.

A big factor is the loss of protective sea ice, which makes the effects of storm waves on the shoreline more severe. Decline of sea ice increases ocean fetch (the distance waves travel uninterrupted) which increases wave height. Decline of shore-fast ice leaves the coast unprotected from waves and more vulnerable to wave action, and as ice coverage decreases so does the damping effect it has on wave action. The effects of sea level rise and storm surges are therefore becoming more destructive than they otherwise would be.

What are Alaskans observing?

What are the facts?

Why are sea level rise and storm surge happening?

Atmospheric scientists say burning of fossil fuels (coal, oil, natural gas) releases “greenhouse gases” into the air, which trap heat that would otherwise escape into space. Some scientists say that the earth’s natural climate cycle also is at work.

What can we do to halt and reverse sea level rise?

Most authorities say that the only solution is using less fossil fuel–based energy wherever possible, driving less, walking more, and using public transport. This is called climate change mitigation. To make significant improvements will require worldwide changes in society and economies, however, and decades or centuries will pass before current trends are completely reversed.

How can we adapt to these inevitable changes?

For more information or assistance