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Glaciers and Climate Change in Iceland: outlook in the beginning of the 21st century Helgi Björnsson Institute of Earth Sciences, Universtiy of Iceland

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Page 1: Glaciers and Climate Change in IcelandGlaciers and Climate Change in Iceland: outlook in the beginning of the 21st century Helgi Björnsson Institute of Earth Sciences, Universtiy

Glaciers and Climate Change in Iceland:

outlook in the beginning of the 21st century 

Helgi BjörnssonInstitute of Earth Sciences, Universtiy of Iceland

Page 2: Glaciers and Climate Change in IcelandGlaciers and Climate Change in Iceland: outlook in the beginning of the 21st century Helgi Björnsson Institute of Earth Sciences, Universtiy

VatnajökullLangjökull Hofsjökull

MýrdalsjökullEyjafjallajökull

Glaciers cover 11% of IcelandThey are rapidly shrinking

Drangajökull

Snæfellsjökull

20 years of precipitation on Iceland

Page 3: Glaciers and Climate Change in IcelandGlaciers and Climate Change in Iceland: outlook in the beginning of the 21st century Helgi Björnsson Institute of Earth Sciences, Universtiy

Firnline

Ablation area

Accumulation area

Ice flow

Runoff

Acquisition of basic data:     Glacier geometry: surface and bedrock      Glacier mass balance      Ice dynamics      Glacio­meteorology      Drainage of meltwater

Modeling:     Mass balance     Ice dynamics     Glacier response to climate

Evaluation of Glacier Evolution

Page 4: Glaciers and Climate Change in IcelandGlaciers and Climate Change in Iceland: outlook in the beginning of the 21st century Helgi Björnsson Institute of Earth Sciences, Universtiy

1995­2007: 10 m     80 km3

accelerating volume loss

Mass balance

Page 5: Glaciers and Climate Change in IcelandGlaciers and Climate Change in Iceland: outlook in the beginning of the 21st century Helgi Björnsson Institute of Earth Sciences, Universtiy

Approach:              Field observations & modelling ⇒ prediction given climate scenarios

Glacier response Glacier flo

w model

Climate scenario

Mass balance model

Page 6: Glaciers and Climate Change in IcelandGlaciers and Climate Change in Iceland: outlook in the beginning of the 21st century Helgi Björnsson Institute of Earth Sciences, Universtiy

0.18 °C/decade0.25 

°C/decade

3.4 mm/decade.

Climate change scenario for Icelandic highland

Page 7: Glaciers and Climate Change in IcelandGlaciers and Climate Change in Iceland: outlook in the beginning of the 21st century Helgi Björnsson Institute of Earth Sciences, Universtiy

Note:Volumes and areas are normalized to present day valuesSpecific runoff is from the present day glacier covered area

Predicted response to CE climate change scenario

Model responses shown for three Icelandic glaciers:Vatnajökull, Langjökull and Hofsjökull

Page 8: Glaciers and Climate Change in IcelandGlaciers and Climate Change in Iceland: outlook in the beginning of the 21st century Helgi Björnsson Institute of Earth Sciences, Universtiy

Year: 2000

Page 9: Glaciers and Climate Change in IcelandGlaciers and Climate Change in Iceland: outlook in the beginning of the 21st century Helgi Björnsson Institute of Earth Sciences, Universtiy

Year: 2050

Page 10: Glaciers and Climate Change in IcelandGlaciers and Climate Change in Iceland: outlook in the beginning of the 21st century Helgi Björnsson Institute of Earth Sciences, Universtiy

Year: 2100

Page 11: Glaciers and Climate Change in IcelandGlaciers and Climate Change in Iceland: outlook in the beginning of the 21st century Helgi Björnsson Institute of Earth Sciences, Universtiy

Year: 2150

Page 12: Glaciers and Climate Change in IcelandGlaciers and Climate Change in Iceland: outlook in the beginning of the 21st century Helgi Björnsson Institute of Earth Sciences, Universtiy

Consequences of climate change

• Glaciers disappear in 100­200 yrs

• Discharge from glaciers increases over next 50 yrs and then decreases

• Seasonal rythm in discharge changes, some rivers disappear

• River discharge = precipitation

• Changes in sediment load of rivers

Page 13: Glaciers and Climate Change in IcelandGlaciers and Climate Change in Iceland: outlook in the beginning of the 21st century Helgi Björnsson Institute of Earth Sciences, Universtiy

Research Program on Glacial Changes in the Himalaya and the Consequences for the Economic and Social 

Development of India

Proposal initiated by the President of IcelandHE Ólafur Ragnar Grímsson

Indus, Ganges, Brahmaputra

Page 14: Glaciers and Climate Change in IcelandGlaciers and Climate Change in Iceland: outlook in the beginning of the 21st century Helgi Björnsson Institute of Earth Sciences, Universtiy

Research Steps toward Prediction of Glacial Changes 

1. Collecting required basic field data2. Develop glaciers models 

– mass balance– physical flow dynamics 

3. Combine mass balance and flow models and run for different climate scenarios

4. Prediction, analyses of consequences and adaptation

• Requires education and training of young scientists ,­ constructive political reactions

Page 15: Glaciers and Climate Change in IcelandGlaciers and Climate Change in Iceland: outlook in the beginning of the 21st century Helgi Björnsson Institute of Earth Sciences, Universtiy

Consequences of Himalayan Gaciers Disappearing in 40­70 years

• Hydrology– Flood hazards, outburst floods– Seasonal changes in river discharge, drinking water, irrigation– Drought– Changing design criteria of bridges and hydropower plants

• Regional planning and development, adaptation, mitigation– Agriculture, food production– Transport – Tourism

• Impact on ecological systems, human health