By Paul Homewood
h/t Athelstan
Still Day One, and the Mail is now onto its second junk climate story of 2018:
An increase of just 2°C (3.6°F) in global temperatures could make the world considerably drier and more desert-like, new research has warned.
More than a quarter of the world’s land surface, home to more than 1.5 billion people, would become more arid and droughts and wildfires could be widespread.
Limiting global warming to 1.5°C (2.7°F) would dramatically reduce the percentage of the Earth’s surface affected, scientists found.
Aridity is a measure of the dryness of the land surface, obtained from combining precipitation and evaporation.
‘Aridification would emerge over 20 to 30 per cent of the world’s land surface by the time the global temperature change reaches 2ºC (3.6ºF)’, said Dr Manoj Joshi from the University of East Anglia’s School of Environmental Sciences and one of the study’s co-authors.
The research team studied projections from 27 global climate models and identified areas of the world where aridity will substantially change.
The areas most affected areas are parts of South East Asia, Southern Europe, Southern Africa, Central America and Southern Australia.
These areas are home to more than 20 per cent of the world’s population – that’s over 1.5 billion people.
The study looked at the current rate of global temperature increase and compared it to data from before the industrial revolution
The world has already warmed by 1°C (1.8°F) since then.
The most affected areas are likely to be parts of South East Asia, Southern Europe, Southern Africa, Central America and Southern Australia. These areas are home to more than 20 per cent of the world’s population – that’s over 1.5 billion people
Read the full article here.
It is probably no coincidence that it is the UEA which has planted this junk science scare story, hot on the heels of the earlier NOAA one.
But in fact many other studies have found that, despite a warmer climate since the 19thC, global drought is not getting worse.
For instance, McCabe and Wolock found in their 2015 paper, Variability and trends in global drought:
Monthly precipitation (P) and potential evapotranspiration (PET) from the CRUTS3.1 data set are used to compute monthly P minus PET (PMPE) for the land areas of the globe. The percent of the global land area with annual sums of PMPE less than zero are used as an index of global drought (%drought) for 1901 through 2009. Results indicate that for the past century %drought has not changed, even though global PET and temperature (T) have increased. Although annual global PET and T have increased, annual global P also has increased and has mitigated the effects of increased PET on %drought.
Time series of the percent of global land area with drought conditions (i.e., annual sums of monthly precipitation minus potential evapotranspiration less than zero).
In 2013, Damberg and Kouchak took a closer look at the last three decades, using satellite observations. They found:
The results reveal no significant trend in the areas under drought over land in the past three decades.
The global trend maps indicate that central Africa, parts of southwest Asia (e.g., Thailand, Taiwan), Central America, northern Australia, and parts of eastern Europe show a wetting trend during the same time span. The results of this satellite-based study disagree with several model-based studies which indicate that droughts have been increasing over land. On the other hand, our findings concur with some of the observation-based studies.
Note that these are the very same areas now claimed by the UEA to be getting drier.
Note also that, whereas the UEA is all climate model based, real observations show the opposite.
And in 2012, Justin Sheffield et al published a paper, Little change in global drought over the past 60 years, whose title says it all.
Significantly, they showed that model based assessments of drought, using PDSI, overestimated potential evaporation, and therefore drought, by not taking into account underlying physical principles, such as changes in available energy, humidity and wind speed.
And as we already know, rising levels of atmospheric carbon dioxide have significantly greened much of the planet in the last 35 years.
And as HH Lamb repeatedly pointed out, it is a colder world that we need to fear, because the equatorial rain systems are squeezed closer to the equator, something that led to the calamitous Sahel droughts and Indian monsoon failures of the 1960s and 70s.
We can safely file this story under J – For Junk!
via NOT A LOT OF PEOPLE KNOW THAT
January 2, 2018 at 06:36AM
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