May 22, 2017

How to lie with statistics: Climate change is turning Antarctica GREEN

Choosing your start and finishing points is a great trick when you want to use statistics misleadingly.  Below they have arbitrarily chosen the last 50 years for their calculations.  And their calculations may be correct.  What they don't say is that all the supposedly causative temperature rise happened in the first (approx.) 30 years of that period.

The most recent 20 years have seen no effect, no change -- the famous "hiatus" during which there has been no statistically significant net temperature rise globally.  So if the greening has continued into the last 20 years -- which they imply -- it is NOT due to global warming. Things that don't exist can't cause anything.  If it has NOT continued into the last 20 years it is a finished trend of no current interest.

I note also that their data was obtained from the extreme end of the Antarctic peninsula, and the peninsula as a whole is known to be anomalous to Antarctica as a whole. It shows occasional warming (probably due to subsurface vulcanism) when the great mass of Antartica is cooling.  The study below is therefore from several viewpoints inadequate to sustain any generalization.  Putting it plainly, it is just another bit of  slippery Warmist propaganda


Few plants live on Antarctica but scientists studying moss have found a sharp increase in biological activity in the last 50 years.

Plant life exists on only 0.3 per cent of Antarctica. However moss is well preserved in chilly sediments.  This offers scientists a way of exploring how plants have responded to such changes.

Scientists gathered data from five ice cores drilled from three islands off the Antarctic Peninsula. They then looked at the top 20cm of each of the cores.

This allowed the scientists to look back over 150 years and explore changes over time. Changes included the amount of moss, and its rate of growth.

They also looked carbon in the plants that indicates how favourable conditions were for photosynthesis at a certain point in time.

The latest study claims the rate of moss growth is now four to five times higher than it was pre-1950.

A team including scientists from the University of Exeter used moss bank cores – which are well preserved in Antarctica's cold conditions – from an area spanning about 400 miles.

They tested five cores from three sites and found major biological changes had occurred over the past 50 years right across the Antarctic Peninsula.

'Temperature increases over roughly the past half century on the Antarctic Peninsula have had a dramatic effect on moss banks growing in the region,' said Dr Matt Amesbury, of the University of Exeter.

'If this continues, and with increasing amounts of ice-free land from continued glacier retreat, the Antarctic Peninsula will be a much greener place in the future.'

Recent climate change on the Antarctic Peninsula is well documented with warming and other changes such as increased precipitation and wind strength.

Weather records mostly began in the 1950s but biological records preserved in moss bank cores can provide a longer-term context about climate change.

The scientists analysed data for the last 150 years, and found clear evidence of 'changepoints' – points in time after which biological activity clearly increased – in the past 50 years.

'The sensitivity of moss growth to past temperature rises suggests that ecosystems will alter rapidly under future warming, leading to major changes in the biology and landscape of this iconic region,' said Professor Dan Charman, who led the research project in Exeter.

'In short, we could see Antarctic greening to parallel well-established observations in the Arctic. 'Although there was variability within our data, the consistency of what we found across different sites was striking.'

The research teams, which included scientists from the University of Cambridge and British Antarctic Survey, say their data indicates that plants and soils will change substantially even with only modest further warming.

The same group of researchers published a study focusing on one site in 2013 and the new research confirms that their unprecedented finding can be applied to a much larger region.

Plant life only exists on about 0.3 per cent of Antarctica, but the findings provide one way of measuring the extent and effects of warming on the continent.

The researchers now plan to examine core records dating back over thousands of years to test how much climate change affected ecosystems before human activity started causing global warming.

The paper, Widespread biological response to rapid warming on the Antarctic Peninsula, is published in the journal Current Biology.

SOURCE.  The academic journal article is "Widespread Biological Response to Rapid Warming on the Antarctic Peninsula"




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