By Paul Homewood
This looks like yet another “worse than ever” junk study!
Droughts in Europe during the summer are more severe now than at any time in the past two millennia, a new study reveals.
Researchers studied ‘chemical fingerprints’ – carbon and oxygen isotopes – in European oak trees to reconstruct summer climate over the last 2,110 years.
They found that drought conditions suddenly intensified in 2015 beyond anything in the past two thousand years, likely due to climate change.
Europe experienced severe summer heat waves and drought spells in 2003, 2015 and 2018, which affected agricultural sectors and the wine and forestry industries.
Europe’s recent summer droughts have had ‘devastating ecological and economic consequences’ – and are set to worsen as the global climate continues to warm.
‘We’re all aware of the cluster of exceptionally hot and dry summers we’ve had over the past few years,’ said study author Professor Ulf Büntgen from the University of Cambridge’s Department of Geography.
‘But we needed precise reconstructions of historical conditions to see how these recent extremes compare to previous years.
‘Our results show that what we have experienced over the past five summers is extraordinary for central Europe, in terms of how dry it has been consecutively.’
Most studies attempting to reconstruct past climates are restricted to temperature – but this team analysed stable isotopes in tree rings.
Chemical characteristics of the rings inside a tree can reveal what the weather conditions were like during each year of that tree’s life.
For the study, Büntgen and his colleagues from the Czech Republic, Germany and Switzerland studied more than 27,000 measurements of carbon and oxygen isotopic ratios from 147 living and dead European oak trees.
The trees, from the genus Quercus, covered a period of 2,110 years, ranging from 75 BC to 2018.
‘Generally, our understanding is worse the further back we go back in time, as datasets looking at past drought conditions are rare,’ said Büntgen.
Over the 2,110-year period, the tree-ring isotope data showed there were very wet summers, such as AD 200, 720 and 1100, and very dry summers, such as AD 40, 590, 950 and 1510.
Despite these ‘out of the ordinary years’, the results show that for the past two millennia, Europe has been slowly getting drier.
The samples from between 2015 and 2018, however, revealed that drought conditions in recent summers have far exceeded anything in the 2,110 years.
I’m always extremely suspicious when I hear claims that weather is far worse than anything in the past, particularly when they cherry pick just three events to make their claim. As these are all random meteorological events, it is inevitable that similar droughts would have happened many times in the last two thousand years.
We should also note this comment:
”Generally, our understanding is worse the further back we go back in time, as datasets looking at past drought conditions are rare”
In other words, they have not got a clue.
It is also hard to understand why they find that the results show that for the past two millennia, Europe has been slowly getting drier. Given the massive swings in European climate from Roman and Medieval Warm periods to the Dark Ages and Little Ice Age, I see no mechanism why it would be getting steadily drier. (We do know though that during the Little Ice Age, summers tended to be wet in Central Europe.)
But, above all, we know conclusively that the climate in Central Europe was much warmer than now for most of the last two thousand years, as confirmed by upper tree lines in the Swiss and Austrian Alps. Under their theory, droughts should have been worse in the past:
HH Lamb: Climate, History and the Modern World pp142
But as always seems to be the case with these sort of studies, they focus on models and ignore real world data. Below are precipitation charts for all of the Czech weather stations with data back to before the war. The charts show rainfall totals during summer.
Not one station shows the slightest evidence that summers are becoming progressively drier, or that recent droughts have been unusual:
These trends are supported by two recent papers, one of which uses data back to 1775. The first finds no significant linear trends in either seasonal or annual rainfall. The second concludes that summer rainfall has increased since 1961.
Only in the world of climate science would “scientists” ignore real world data, and instead believe tree rings. They’ll be reading tea leaves next!
via NOT A LOT OF PEOPLE KNOW THAT
March 17, 2021 at 06:00AM