north atlantic warming

We have all heard the stories about global warming and the fact that effects are greater in the northern reaches of the American and Eurasian continents. The upper part of the North Atlantic has also tended to show stronger warming but the last sea surface temperature anomalies map from NOAA is particularly revealing. Most of the expanse between Ireland and Canada's east coast is 2 degrees above the long term average with a large area east of newfoundland even up by 3 degrees. Given that sea temperatures fluctuate a lot less than land temperatures this sounds like a lot to me. The North Sea has been found to have warmed by 1 degree over the past 25 years and northward motion of fish and plankton species has been ascribed to this. The North Atlantic is not prime dive territory but what happens up north doesn't necessarily stay up north.

Bart

I don't know if it's related to global warming or pollution or what but I'm seeing dramatic changes to the underwater and seacoast life off of New England. Metridium anemones uses to be one of the most common sights here locally. They have all but disappeared. There have been massive die-offs of the grasses that make up the tidal marshes.

This is getting very disturbing. Maybe we are nearing a tipping point for the ocean as we know it.

Thanks for the local observations, they sound rather extreme and worrisome indeed. I believe in an older thread there were reports of new species sighted along the west coast of the British isles as well as the waters of Norway. It may not be too long before you can start seeing lionfish in New England. I understand they have already made it up to Long Island.

Bart

We have also found new species in the few last year here in Iceland, At least 2 species of fish are now part of the ecosystem now, that where not living here 5years ago. We have found one new crab species a year ago.

And we have seen sea life are chancing.

Last week I filmed two Common Remoras attached to a dead leatherback turtle off South Wales in the UK. Whilst a rare sighting, these are within their known range (remoras have been recorded from as far north as Iceland), but it will be interesting to see if the number of sightings of fish like these will increase with the warmer water as such fish are generally considered to be a warm water species.

The weekly update of sea surface temperature anomalies showed that the region of warming has increased again. Almost the entire area of the North Atlantic is now 2 degrees warmer than the long term average and the area with +3 degree temperature deviation has extended to the east (NOAA).

There is also a site with data for more northern latitudes (here) which shows a whopping 5 degree of warming off the northern shores of Canada and Siberia. No wonder that the arctic ice sheet has collapsed this year as you've probably read or seen on the news. In recent years arctic ice melting has accelerated by a factor of 2 and the arctic is now expected to be ice free in late summer as early as 2030-2040. Just this year, the minimum icepack decreased from its past 2005 record low of 5 million sq.km to 4 million sq.km last week, and the minimum for 2007 has probably not yet been reached.

The disappearing ice no longer reflects solar heat which contributes to the exceptional warming seen for the northern latitude waters. As the arctic waters warm it takes longer before winter ice starts expanding again, resulting in a shrinking icepack maximum in March. 2006 had the smallest March ice pack in recorded history with 2007 a close second. This feedback loop probably explains the observed acceleration of the melting process.

Does this affect me today, no. Will it affect me in the future, don't know for sure. Still, one of the reasons for the success of Homo sapiens is its ability to change behavior in response to changing environments. The question is, will we change behavior based on the early warning signals given by climate models or will we wait and respond to events as they happen. So far it seems we are following plan B.

Bart

has anyone got any long reaching data regarding temperature fluctuation in the southern hemisphere? it would appear by the graph in the orignial post that ANTARCTICA is sporting lower temps.

it would be interesting to know if there is any correspondence in fluctuation between the two poles.

mark

Hi Mark,

I haven't seen long-term raw data but the general idea is that the southern hemisphere is much less impacted by global warming so far. It is my understanding that this is due to the fact that the great majority of the land mass is in the northern hemisphere. South of Australia (and that corresponds to San Francisco or so in terms of distance-from-the-pole) there really isn't that much land apart from antarctica itself. Temperatures over land increase more rapidly than over water and the albedo effect is also no real issue in the southern hemisphere until antarctica itself starts falling apart and so far much of the south pole has stayed cold enough to not show much thawing. The greenhouse concept, if correct, should still apply but warming will be slower than in the north just like cooling during ice ages always seems to have mostly affected north America and north Eurasia.

Bart

Just to add to Paul's comment, my daughter snorkelled with a small basking shark while we were in Western Scotland in August and it had a remora attached.

Jim

I believe that a Basker complete with a Remora was spotted off Lundy Island in the Bristol Channel this summer too! Remoras were apparently recorded quite frequently when there was a shark fishery off southern England, but whether records are simply rarely made or whether there are now more of them is a tricky question to actually answer, from the research that I've been doing.

Jim

 

I believe that a Basker complete with a Remora was spotted off Lundy Island in the Bristol Channel this summer too! Remoras were apparently recorded quite frequently when there was a shark fishery off southern England, but whether records are simply rarely made or whether there are now more of them is a tricky question to actually answer, from the research that I've been doing.

Hi Paul. If you look at the basking shark footage on my site, from Cornwall 2006, you can clearly see at least 4 remoras on one of them. Having said that we are definately seeing changes in species, and their number and duration seasonal species hang around for.

Cheers

Colin