Tag Archives: David Aldridge

Scientists observe what might happen if ocean circulation slows

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Map of Europe showing the differences in temperature between 11–18 December 2009 and the 2000–2008 average.

If you are sat in a cold bath and turn on the hot tap, what happens? The water close to your feet becomes unbearably hot and the water near the top half of your body doesn’t noticeably change temperature. Fundamentally, the same process happens in the oceans. The sea nearest to the equator heats up as it receives the highest amount of energy from the sun; the sea nearest to the poles generally loses heat. In the bath, you slosh the water about as it enters the tub to distribute the heat more evenly. In the oceans, currents perform the same job, helping to move heat from the equator to the poles and make higher latitudes more habitable. If, for some reason, the currents transporting heat to higher latitudes slowed, the effect would be similar to you not mixing your bath water. Your feet (the equator and tropics) would become hotter, and your body (the subtropics and poles) would become colder. This is exactly what scientists think they observed in 2009/2010 in the North Atlantic, and they think this may explain some of the freak weather that was observed during that period.

Continue reading Scientists observe what might happen if ocean circulation slows

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Phytoplankton waiting game perhaps key to their success in ocean deserts

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File:Survival Technique.JPGIn survival situations people often talk about the rule of three. It is said that humans can only survive for 3 minutes without air, 3 hours without heat, 3 days without water and 3 weeks without food. Not wanting to be left out, it seems that some phytoplankton also obey a rule of 3 according to a new study: they can survive for 3 weeks without key nutrients such as nitrogen and phosphorus.

Continue reading Phytoplankton waiting game perhaps key to their success in ocean deserts

Ocean Deserts: it’s a hard life in the tropics, but not if you’re small

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Subtropical gyres are an extreme environment that covers approximately 30 % of the planet’s surface

Think of an extreme environment where life survives in the ocean. What springs to mind? The mind boggling pressures and eerie quiet of the deep-sea perhaps? Maybe the icy environments at the poles? Possibly even an estuary, where organisms are flung from one salinity extreme to the other on a daily basis. There is another extreme environment though, one which few of you probably even considered, one that covers about 30% of the planet and is currently expanding under the influence of climate change: large swirling systems of rotating currents that occur in the centre of oceans known as subtropical gyres.  Continue reading Ocean Deserts: it’s a hard life in the tropics, but not if you’re small

5 reasons why dinoflagellates are friggin’ awesome:

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Dinoflagellates are large single-celled motile phytoplankton that are extremely widespread and abundant in the ocean. They are astonishing little creatures that – depending on the species – can produce potent neurotoxins, feast on organisms many times larger than themselves (whilst also photosynthesising), travel large distances in search of nutrients, hibernate for up to 100 years, and glow with terrific blue-coloured bioluminesence. So, without further ado, here are five reasons why dinoflagellates are friggin’ awesome: Continue reading 5 reasons why dinoflagellates are friggin’ awesome:

‘Twas the night before Christmas (phytoplankton edition)

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A reworked (some would  say ‘improved’) version of  Clement Clarke Moore’s classic Christmas poem:

christmas plankton‘Twas the night before Christmas, and all through the ‘photic zone,
Few creatures were stirring, most plankton were all alone;
The water was mixed, with nutrients galore,
Critters hoping come spring, temperatures would soar. Continue reading ‘Twas the night before Christmas (phytoplankton edition)

Calcifying plankton and climate change

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Most of you reading this will be very familiar with the story of how ocean acidification is likely to impact marine calcifying organisms: increased carbon dioxide in the atmosphere is decreasing the pH of the oceans and is proposed to eventually lead to the dissolution of the shells of organisms made from calcium carbonate. It is difficult to work out in the lab, however, exactly what the impact of ocean acidification will be on marine calcifiers, as time pressures favour experiments that only assess short-term acclimation responses of organisms to ocean acidification (rather than long-term potential adaptations). Even when long term experiments have been carried out, they have only looked at the impact of pH change alone (see here), ignoring other relevent variables such as temperature. Continue reading Calcifying plankton and climate change

A guide to iron fertilisation of the ocean

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Image 1: A satellite image of the supposed iron-induced phytoplankton bloom. It seems to attribute all elevated chlorophyll concentrations in the region to the experiment. Chlorophyll is naturally patchy in its distribution, so this image is less than useless (especially as they didn’t even provide satellite images from before the dump!).

It was revealed this week that Russ George, a controversial American Businessman (Deep-Sea News ran a good piece this week covering his chequered history), dumped around 100 tonnes of “iron-rich dirt-like material” off the west coast of Canada in July in order to “gather data targeting all the possible fears that have been raised” about ocean fertilization – an act that is in violation of two international moratoria designed to prevent material from being dumped in the ocean. Judging from the poor quality of news coverage on the issue, which tended to include the deceptive image shown above (Image 1), there are a lot of misconceptions about iron fertilisation of the ocean. Here is the official Words in mOcean idiot’s guide to make you instantly more knowledgeable on this subject. Continue reading A guide to iron fertilisation of the ocean

Gone with the wind: perspectives on offshore wind power

This debate, which took place at the Challenger 2012 marine science conference in Norwich, consisted of four speakers with a broad range of expertise including industry, public perceptions, marine and bird life impacts. Each speaker gave a brief presentation, which is summarised; a question and answer session followed this.

Industry perspective – Paul Reynolds: Development manager at RenewableUK (the trade and professional body for the UK wind and marine renewables industries) Continue reading Gone with the wind: perspectives on offshore wind power

A selection of short talks from Challenger 2012

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There were over 100 talks at this year’s Challenger 2012 conference. We have already covered four of the keynote lectures by Jorge Sarmiento, David Righton, Ken Buessler and Phyllis Lam. Below are summaries of some of the short talks that took place: Continue reading A selection of short talks from Challenger 2012

Challenger 2012 (Selected keynote lectures): Ken Buesseler (Woods Hole Oceanographic Institution) – Controls on and variability in particle export and flux attenuation in the ocean’s twilight zone

The 15th Biennial Challenger Conference for Marine Science recently took place at the University of East Anglia in Norwich, on 3-6 September 2012. There were over 100 talks, 150 posters, a contentious debate on wind power, and a talk on how the UK can maintain its current research infrastructure. Over the next week or so Words in mOcean will be bringing you a recap of the best of the action, starting with four of the keynote lectures. Today’s recap is on the lecture given by Ken Buesseler, titled ‘Controls on and variability in particle export and flux attenuation in the ocean’s twilight zone’. Enjoy! Continue reading Challenger 2012 (Selected keynote lectures): Ken Buesseler (Woods Hole Oceanographic Institution) – Controls on and variability in particle export and flux attenuation in the ocean’s twilight zone