Philipp SemenchukElisabeth CooperBo ElberlingUniversity of Tromsø, Arctic and Marine Biology

University Center in Svalbard (UNIS)

University of Copenhagen, Center of Permafrost (CENPERM)

23 May 2013

Ecosystem respiration patterns in the high Arctic are subject to change

CO2

2

Ecosystem respiration background

Implications on global climate

This presentation focuses on how global warming can change natural CO2 emissions from Arctic tundra

Time

Atm

osph

eric

con

cent

ratio

n of

CO 2

1960 1970 1980 1990

320

330

340

350

360

Maunaloa monthly

Temperature changes and respiration

3

CO2 emissions can be increased with warming

Ecosystem respiration is mainly dependent on temperature

Soil temperature

Eco

syst

em r

espi

ratio

n

0

5

10

15

20

-10 0 10 20

Temperature

Resp

iratio

n

4

Better and more substrate more respiration

Ecosystem respiration is also dependent on substrate (=food for microorganisms)

5

Microbes are picky eaters: best substrates disappear quickly, worst substrates slowly

Interaction with temperature.Not only food, but all biological material!

The Arctic is cold, but warming up

7

Winter soil temperatures change with snow thickness

Fences increase snow depthSnow insulates soil

8

Best substrates are used up after 5 years of warm winters Te

mpe

ratu

reRe

spira

tion

Date

9

Increased CO2 production during warmer winters could influence global CO2 concentrations

Time

Atm

osph

eric

con

cent

ratio

n of

CO 2

1960 1970 1980 1990

320

330

340

350

360

Maunaloa monthly

~20% of worlds C reserves

10

Microbes are picky eaters!

However, tundra is a huge fridge (~20% worlds carbon)…

Questions?

In conclusion, increased winter temperatures might change whole year ecosystem respiration patterns in the Arctic