'An ocean full of eddies'

from Deep Sea News:

'Severely disquieting'

'A century of phytoplankton decline suggests that ocean ecosystems are in peril.'

Tom Goreau says:

This report is correct, but as usual it is not new. In some of our papers on global satellite sea surface temperature trends published 5 years ago we point out that the places in the ocean we have identified that are warming faster than average are also the places where phytoplankton chlorophyll are decreasing, due to the thicker warm surface layer getting so thick and buoyant that upwelling of nutrients is being blocked, indeed we identified major fisheries regions where the upwelling has stopped and the fisheries are collapsing from the bottom up. There are also much smaller areas where the phytoplankton are increasing, and those are remote areas where the wind speed has increased, but the gains in those places are far less than the losses. This problem will increase with time.

P.S. 2 Aug: a colleague refers to SAHFOS which carries a link to a summary of recent research into the question of whether climate change and biodiversity of marine plankton in the North Atlantic could affect the carbon cycle.

A relevant paper by Goreau et al is here.

P.S. 6 Aug: Bill McKibben puts his spin on the findings.

Ocean deoxygenation

The appearance of large zones of low-oxygen or no-oxygen along exposed outer coasts like Oregon and Washington came as a complete surprise. If someone had told me this rich, diverse, productive ecosystem could rapidly become a ‘dead zone’, I would have thought they were nuts. And yet we’ve seen the seasonal appearance of hypoxia in 6 of the last 6 years. Francis Chan’s close examination of all data on dissolved oxygen from the last 6 decades off the Oregon coast gives a sense of how very bizarre the last 6 years have been. The data show that the normal situation off our coasts is well oxygenated waters, with only 1 of 10,000 records showing any hypoxia. The recent transformation of this ecosystem from one dominated by a diverse assemblage of rockfish, crabs, sea stars, anemones, sea cucumbers, flatfish, lingcod and more to one devoid of life except microbes has been stunning, wholly unexpected and downright scary. We know that many of the fish and some of the crabs seem to be able to swim or scuttle away from the low-oxygen waters, and in some cases they reappear once the levels of oxygen return to normal, but we do not know the long-term consequences of an annual die-off of the habitat-forming, bottom-dwelling species, many of which live to be decades old.

-- Jane Lubchenco

(See also ocean suffocation?)

'Ocean suffocation'?

Last night I created a stub on Wikipedia for ocean suffocation, and it has survived at least to the time of writing this.

The purpose was to help highlight for non-specialists a phenomenon that may prove to be important. As noted here, Ralph Keeling has suggested 'ocean oxygen deprivation'. But it's not clear to me that 'ocean suffocation' is any less accurate or more sensational than, for example 'ocean acidification', which is now a widely accepted term.

Anyway, this needs attention from people better-trained and wiser than me.

P.S. 24 Oct: After discussion involving distinguished oceanographers and others the wiki stub is now labeled ocean deoxygenation.

'Poised for significant reorganisation'

Scientists fear 'tipping point' in Pacific Ocean - a media report on a paper titled Emergence of Anoxia in the California Current Large Marine Ecosystem.