Global climate change has regional implications and regional impacts –

extraction from the ocean chapters of IPCC WGII AR5

SICCME Open Session. ICES ASC, A Coruña, Spain SICCME Open Session. ICES ASC, A Coruña, Spain 17 September 201417 September 2014

Svein Sundby

Impacts of global climate change on the ocean physics Impacts of global climate change on the ocean physics and chemistry:and chemistry:

1.1.Getting warmer Getting warmer 2.2.Losing oxygenLosing oxygen3.3.Acidifies and increase in subsaturation of calcium Acidifies and increase in subsaturation of calcium carbonate carbonate

General consequenes for marine ecosystems:General consequenes for marine ecosystems:

1. Change in productivity1. Change in productivity2. Displacement of species2. Displacement of species3. Changes in species diversity and structure and 3. Changes in species diversity and structure and functioning of the ecosystemsfunctioning of the ecosystems

6. Subtropical gyres6. Subtropical gyres5. Eastern boundary upwelling5. Eastern boundary upwelling4. Coastal upwelling4. Coastal upwelling

1. Spring-blooms1. Spring-blooms 2. Equatorial upwelling2. Equatorial upwelling 3. Semi-enclosed seas3. Semi-enclosed seas

7. Deep Sea7. Deep Sea

World oceans composed of a diverse set of ecosystems –World oceans composed of a diverse set of ecosystems –IPCC WG2 Ch 30 has considered 7 major groups:IPCC WG2 Ch 30 has considered 7 major groups:

Figure 30.1 aFigure 30.1 a

20 % of the 20 % of the world world

ocean’s areaocean’s area

80 % of the 80 % of the world’s fish world’s fish

catchescatches

Globally modeled phytoplankton production(average of a group of four global models)

Steinacher et al. (2010) Biogeosciences

Pre-industrial production(1860s)

Change in production at the end of this century (2090s)

Physical processes regulating primary productionPhysical processes regulating primary production

IPCC (2014)

De subtropiske virvlene

Vind

Assumed critical factor for primary production:

Global warming increases thermal stratification and reduces vertical flux of nutrients

> Reduced primary production

The Subtropical gyres ”The Deserts”

Østlige oppstrømningssystemer

Assumed critical factor for promary production (the Bakun hypothesis):

Global warming increases the thermal gradient between land and ocean giving increased wind and in turn increased flux of nutrients from the depth

> Possible increased primary production

Eastern Boundary Upwelling Ecosystem

Våroppblomstyringssystemene

Temperature

Lysbegrenset

Næringssaltbegrenset

Temperaturbegrenset

Vind

Kritisk faktor ved klimaendringer

Assumed critical factor for primary production:

Global climate change increases the ocean temperature giving increased regenerated production.

> Increased primary production

The high-latitude spring-bloom ecosystems

Reduction in oxygen concentration will primarily impact areas that have additional low-oxygen natural/anthropgenic stress

Figure 30.9 bFigure 30.9 b

Low-latitude coastal regions and semi-enclosed seas(e.g. Baltic, Black, and Mediterranean)

Figure 30.7 a og bFigure 30.7 a og b

2 oC target

”Business as usual” Shellfish

Invertebrates

Vertebrates

ACIDIFICATIONACIDIFICATION

Figure 6.14Figure 6.14

Global climate change causes redistribution of species:Global climate change causes redistribution of species:

Reduction at low latitudes, increase at high latitudesReduction at low latitudes, increase at high latitudes

ICES Working Group on Widely distributed Stocks (WGWIDE).

Icelandic-Faroese-Norwegian cruise trawl survey on mackerel (Nøttestad et al. 2013)

Atlantic mackerel

From EU and Norway

to Iceland, Greenland

…and Russia?

Adaptation and mitigation for marine ecosystems?

* Reduce international conflicts: Develop commonly accepted rules for shared stocks under distributional changes

* Continue to develop ”ecosystem-based management of fish stocks

* Replace coral bleaching by warm(est) water species (e.g. from the Arabian Gulf)

”Climatic changes in the Arctic in relation to plants and animals”

Preface by Gunnar Rollefsen with Appendix: Enquiry into the Problem of Climate and Ecological Changes in Northern Waters

Introductory address by Hans W:son Ahlmann

A. Contribution to Physical Changes

Recent Climatic Fluctuations by Leo Lysgaard

The increase in the Sea Temperature in Northern Waters during Recent Years by Jens Smed

B. Contributions on Biological changes

On Changes in the Marine Fauna on the North- Western Atlantic Area, with special reference to Greenland by Å. Vedel Tåning

Boreo-tended Changes in the Marine Vertebrate Fauna of Iceland during the last 25 years by Arni Fredriksson

Fluctuations in the two most important Stocks of Fish in Northern Waters, the Cod and the Herring by Gunnar Rollefsen

On Changes inthe Distribution of Terrestrial Animals in Relation to Climatic Changes by Poul Jespersen

The Forecasting of Climatic Fluctuations and Its Importance to the Arctic Fisheries by Arthur Lee

?

Development of Barents Sea temperature

observations, 30-yr low-pass filter of observations, and modelled anthropogenic component