Can we imagine a World without Ice?

Climate change: Impacts on glaciers

Helgi BjörnssonInstitute of Earth Sciences, University of Iceland

2,15%

97,2%

0,001%

0,63%

0,01%

Glaciers in the hydrological cycleWhat is at stake?

Global sea level riseGlobal sea level rise

Depending on climate scenarios

IPCC 2007

0.2 – 0.5 m ?

IPCC AR4

1961-2003 1993-2003

3.1 +/- 0.7 mm year-1

Varmaútþensla

Thermal expansion

Jöklar utan heimskauta

Glaciers outside polar regions

Greenland

Antarctica

Contributions to rising sea level

?

?

Sea level equivalent: 61.1 m

SLE: 7.2 m

SLE 0.5 m

Glaciers in polar regionsSea level equivalent: SLE 69 m

Canadian Arctic islandsCanadian Arctic islandsArctic islands of N-Europe Arctic islands of N-Europe

(Spitsbergen, Novaya Zemlya)(Spitsbergen, Novaya Zemlya)

GreenlandGreenland

SLE: 7.2 mSLE: 7.2 m

AntarcticaAntarctica

SLE: 61.1 mSLE: 61.1 m

Melting of the ice cover on the Arctic Ocean

The most visible expression of global warming

1979 2005

Of global importance for ship-transport of goods and cargo

Arctic glaciological research require international collaborationArctic glaciological research require international collaboration

Muli-national collaboration of Arctic research

Impact of climate change in the Arctic

• Substantial decrease in Arctic Sea Ice, thinning and reduced area• Amplified by reduced albedo

• Thawing of permafrost, release of methane

• Extinction of many organisms that are adapted to this habitat, endemic species.

– What are the walrus going to eat if they have to come ashore in the summer?

• Models predict:– 5 cm sea-level rise from melting in Greenland during the 21st

century.Greenland may almost completely melt during the next 1,000 years (starting melting rapidly by 2100).

New ZealandNew Zealand

PatagoniaPatagonia

PyreneesPyreneesAlpsAlps

The Third The Third PolePole

AlaskaAlaska

Pacific Coastal Pacific Coastal RangeRange

Rocky MountainsRocky Mountains

IcelandIceland

Mid-latitude glaciersSea level equivalent: SLE 0.5 m

NorwayNorway

Glacier changes in The Tibetan Plateau and the Himalaya region have economical and social impact on more than 1000 million people

Indus

Ganges

Brahhmaputra

SalweenYangtze Mekong

Yellow river

Third-pole glaciological research require international collaboration

Tropical glaciers

EcuatorEcuatorBoliviaBoliviaNorthern Northern AndesAndes

New Guinea, New Guinea, IndonesiaIndonesia

Kilimanjaro Kilimanjaro Mount KenyaMount Kenya

HydrologySeasonal runoff changes. Excessive Flooding. Water arrives earlier than needed Glacial lakes outburst floods (e. g. Nepal, Bhutan) Sediment transportReplenishment of reservoirs for drinking supplies, domestic use, Irrigation, droughts (e. g. Mongolia, western China, Pakistan, Afghanistan, India, Tajikistan, South America).

Societal matters, regional planning, geoengineering Development, adaptation Engineering and transportation, design of roads, bridges, hydropower plants, Tourism, ski resorts, mountain recreation. Food production, Reduced Agricultural Output Public health Political conflicts

Ecosystems Animal, Bird, and Fish Habitat Loss. – Plants.

OceansSea level rise, effect on coastal regions worldwide.Alterations to the ocean currents, thermohaline circulation.Longer term albedo changes, climate feedback.

Impacts of glacier retreat on:

The Ocean’s Conveyor Belt

ColdCold

Warm

Iceland is located at the border of warm and cold ocean and atmospheric Iceland is located at the border of warm and cold ocean and atmospheric currentscurrents

Heavy precipitation

Mild tempeartures

Global sea level riseGlobal sea level rise

New predictions

0,8 – 1 m ?

Potential dynamic instability of landbased glaciers is not considered in the present IPCC report May contribute < 2 m before 2100.