Cryosphere hazards from the perspective of

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22 Φεβ 2014 (πριν από 3 χρόνια και 6 μήνες)

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Cryosphere

hazards from the perspective of
a State Agency

Gabriel Wolken

Alaska Division of Geological & Geophysical Surveys

3354 College Road, Fairbanks, Alaska 99709
-
3707

Ph:
907.451.5018

Fax: 907.451.5050

email: gabriel.wolken@alaska.gov

web:
www.dggs.alaska.gov

Alaska DGGS


Hazards

Programs


Climate Change Hazards (CCHP)


Geohazards

Evaluation and Geologic Mapping for Coastal
Communities

06/13/2011

Workshop on Snow, Ice, and Permafrost Hazards

2

Flooded permafrost cellar near the
Wulik

River, NW Alaska



Hazards assessment and
evaluation


Information management and
dissemination


Promoting Public awareness


06/13/2011

Workshop on Snow, Ice, and Permafrost Hazards

3


Glossary of Hazards


Hazard Types


Published Maps and Reports


Found at:

http://www.dggs.dnr.state.ak.us/


Engineering geology>Guide to
geologic hazards in Alaska


Guide to Geologic Hazards in Alaska

06/13/2011

Workshop on Snow, Ice, and Permafrost Hazards

4

State of Alaska Statute AS 41.08.020


Alaska

Division of Geological & Geophysical Surveys


“...determine the … potential geologic hazards to
buildings, roads, bridges, and other installations and
structures.”


What is a hazard?


Hazard
: an exposure to a natural geophysical process that
adversely affects people, property, or infrastructure



Risk
: the likelihood of the hazard

x

its adverse consequence

06/13/2011

Workshop on Snow, Ice, and Permafrost Hazards

5

Natural Processes

Natural Hazards

Photo: N. Kinsman

Alaska and the
Cryosphere

06/13/2011

Workshop on Snow, Ice, and Permafrost Hazards

6

Alaska and the
Cryosphere

06/13/2011

Workshop on Snow, Ice, and Permafrost Hazards

7

Flooded permafrost cellar near the
Wulik

River, NW Alaska

R.
Reger

Thermokarst

and bike path in Fairbanks, AK

A. Gal

Ice Bridge across the Chena River, Fairbanks, AK

P. Carter

Avalanche on the Richardson Highway

Alaska and the
Cryosphere

06/13/2011

Workshop on Snow, Ice, and Permafrost Hazards

8


Flooding and erosion affects 184 out of 213, or 86 percent, of Alaska Native villages to some extent (US
Government Accounting Office Report GAO
-
04
-
895T).


71 percent of Alaska coastal communities, or 80 out of 112, sit at or below 10 meters elevation.

Changes in Climate

06/13/2011

Workshop on Snow, Ice, and Permafrost Hazards

9

C
hanges in climate can modify or

intensify natural processes that lead to hazards

Changes in Coastal Processes

06/13/2011

Workshop on Snow, Ice, and Permafrost Hazards

10


Decreased sea ice extent and duration


Reduced shore protection


Increased fetch


Storm surges


Increased sea surface temperatures


Thermal abrasion


Increased sediment load


Accelerated
thermokarst

development


Increased lagoon and tidal prism
volumes


Erosion


Sea level rise


Inundation of low
-
lying areas




Photo: J Mitchell

Photo: J Mitchell

Kivalina

Changes in Alaska’s Northern Region

06/13/2011

Workshop on Snow, Ice, and Permafrost Hazards

11


Coastal erosion may have doubled since 1955


Inland expansion of channel networks and
increased river bank erosion have been
attributed to warming


Lakes, ponds, and wetlands appear to be more
dynamic, growing in some areas, shrinking in
others, and changing distribution across lowland
regions


Permafrost degradation on the Arctic coastal
plain suggests 10
-
30 percent of lowland and
tundra landscapes may be affected by even
modest warming


Slope instability in headwater regions is
increasing and leading to increased
sedimentation rates


Photo: USGS

Changes in Alaska’s Glaciers

06/13/2011

Workshop on Snow, Ice, and Permafrost Hazards

12


During the 20
th

and 21
st

centuries, most land
-
terminating glaciers in Alaska retreated
extensively from their Little Ice Age maximum
extent


Since 1980, nearly all glaciers in Alaska have
been in a state of retreat


Contributing significantly to sea level rise


Changes in water availability and
sedimentation rates will impact:


Water supplies


Water quality


Hydroelectric power generation potential


Flood hazards


Freshwater, estuarine and coastal habitats

Cryosphere

Hazards and Alaska

06/13/2011

Workshop on Snow, Ice, and Permafrost Hazards

13

Photo: AK DCRA

Shishmaref


C
hanges in climate can modify or

intensify natural processes that
lead to hazards



Natural hazards in the
Cryosphere

can cause casualties and severely
damage property and
infrastructure



Numerous threatened
communities in Alaska are
currently involved in mitigation or
adaptation efforts in response to
Cryosphere

hazards



Informed community decision
making requires accurate and up
-
to
-
date baseline
geoscience

data


Cryosphere

Hazards Investigations


Establish a collection of
baseline
data


Hazards assessment and
evaluation


Existence, changes, and potential


Promote
public awareness

of
hazards and educate the public
about specific hazards in their
area


Provide critical information to
decision
-
makers for use in
community planning and risk
management


builds capacity at all levels



helps communities mitigate or
adapt to the impacts of hazards

06/13/2011

Workshop on Snow, Ice, and Permafrost Hazards

14

Knowledge Gaps and Issues of Concern

06/13/2011

Workshop on Snow, Ice, and Permafrost Hazards

15

It’s Alaska…



B
aseline data are sparse,
limed
duration, or nonexistent



Access to data

is challenging



Hazard assessments are not
performed
regularly or routinely


Limited financial resources


Causal links are equivocal



Lack

of
communication

among
scientists

and few
collaborations



Lack of an

efficient method for
coordinating activities, prioritizing