Reporting in Geophysical Research Letters, the authors attribute the reversal to a weakened Arctic Oscillation, a major atmospheric circulation pattern in the northern hemisphere. The weakening reduced the salinity of the upper ocean near the North Pole, decreasing its weight and changing its circulation.
Increasing melting of polar ice would also reduce surface salinity, so whilst I\'m not saying they are wrong that its a natural cycle, it could still be due to warming.
Herein lies the real problem with global climatic change \'science\', its impossible to apply the falsificationist approach, to do so I would need a few replicate earths and then I could manipulate the human population on replicate groups, THEN I could scientifically tell you what was going on.
We can\'t do this, so we are dealing with a phenomonally complex system, which any number of models may explain what we are seeing, and we have no way of testing which is true.
This also highlights another problem, just because something is natural doesn\'t mean it is either good or that we shouldn\'t do something about it. Katrina was natural, would you have stopped that if you could?
This one worried me:
A climate change timebomb may be just 10 years away from detonating, according to the latest global warming evidence.
New data from a deep ice core drilled out of the Antarctic permafrost reveal a shocking rate of change in carbon dioxide concentrations.
The core, stretching through layers dating back 800,000 years, contains tiny bubbles of ancient air that can be analysed.
Scientists who studied the samples found they left no doubt as to the extent of the build-up of greenhouse gases.
For the past 800,000 years, carbon dioxide levels had remained at between 180 and 300 parts per million (ppm) of air. Now they are at 380ppm.
Dr Eric Wolff, from the British Antarctic Survey, who presented the findings at the BA Festival of Science in Norwich, said: \"The rate of change is the most scary thing. We really are in a situation where something\'s happening that we don\'t have any analogue for in our records. It\'s an experiment we don\'t know the result of.\"
Many experts recognise a \"tipping point\" of 440ppm of carbon dioxide, after which climate change starts to run out of control.
The ice core also showed a doubling in concentration of the second most important greenhouse gas, methane, in the last 200 years.
Professor Peter Smith, from the University of Nottingham, said there was an \"urgent need\" to find new technologies to reduce the impact of human activity on climate.
\"Governments may have only 10 years in which to determine the destiny of our planet - giving only five years in which to develop feasibility and design studies,\" he said.
As far as I\'m concerned, anyone who doesn\'t recognise that something bad is happening has their head stuck in the sand.