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Showing posts from 2010

Delving in Antarctica

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‘It is almost a reproach to civilization that we have arrived at the close of the nineteenth century without knowing the whole of the superficial appearance of this planet,’ declared an exasperated John Sutherland, Duke of Argyll and former Governor of Canada, in 1897. In spite of the huge progress made across science, technology, engineering and social reform during the Victorian era, the area surrounding the South Pole was unknown. Yet by 1913, a concerted push by the likes of Shackleton and Scott for Britain, Amundsen for Norway, Mawson for Australasia, Filchner for Germany and Shirase for Japan, had reached the South and flung open the door on Antarctica. A frozen continent shaped by climatic extremes and inhabited by wildlife and vegetation unknown to science was being uncovered.
We now know Antarctica and the surrounding Southern Ocean play a hugely significant role in our planet’s climate. By helping regulate the global exchange of heat and carbon dioxide, subtle changes in the …

Logging old weather

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Ever since the first Royal Navy vessels set forth to patrol the high seas, its ships have kept meticulous records of the weather. By the 1670s, the might of the British Empire was religiously keeping detailed observations on the state of the elements on and in the world’s oceans. Even during battle, ship crew members would be sent off to make a remarkable suite of measurements, including air and sea temperature, wind direction and speed, and air pressure. Dodging shrapnel hurtling through the air, these observations were diligently put into log books to help forecast the conditions individual ships might face in the near future. Even in the nineteenth century, however, it was realised there was considerable scientific value to this work beyond the immediate need of prediction. One of the most vocal supporters of their expanded use was the Rear-Admiral and great British scientist, Sir Francis Beaufort. Beaufort is best known today for his development of a scale that allows an estimatio…

The global impact of ocean cooling in the 1960s

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A common complaint made by so-called climate sceptics is the fact that global temperatures haven’t precisely tracked the trend of rising greenhouse gas levels over the twentieth century. The argument seems to be that if carbon dioxide emissions are a significant driver of climate change then temperatures should have inexorably risen over the recent past. The assumption behind all this is that natural processes don’t have any major effect on hemispheric or global temperatures. Recent published work shows this just isn’t the case.
When we look at data collected by weather stations since the nineteenth century, we find the world’s temperature has increased by around 0.8 °C. This may not sound much but the average for the planet hides a complex mix of regional warming and cooling in different places over different times. The sceptics have picked up on the fact that in spite of the long-term trend, there hasn’t been a constant upward drift. The early increase in temperature up to the 1940s …

A lesson from past global warming

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When looking to the future, it’s only natural to scrutinise yesterday. Be it studying the form of a favoured racehorse, probing twentieth century economic trade figures or analyzing international diplomatic relations over the centuries, history offers an insight into what might lie ahead. But written records aren’t our only source of information when we wish to learn from the past. Geology can serve a similar purpose when looking at climate change. Although the timescale may seem interminably long, records of our planet’s environment, preserved within rock, mud and ice (often referred to as ‘natural archives’ within scientific journals), can extend historical testimony and provide unique insights into the climate of our planet and where things might be heading in times to come. The question is how? To look at one example from the past, let’s ignore virtually all of the 4.5 billion years of our planet’s history and concentrate on only the most recent sliver of time. 
Over the last centu…