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.
In 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.
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→
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:→
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→
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→
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.