BBC’s 50C Days Rubbish

From NOT A LOT OF PEOPLE KNOW THAT

By Paul Homewood

h/t Ian Magness

The BBC are now making it up as they go along!

The number of extremely hot days every year when the temperature reaches 50C has doubled since the 1980s, a global BBC analysis has found.

They also now happen in more areas of the world than before, presenting unprecedented challenges to human health and to how we live.

The total number of days above 50C (122F) has increased in each decade since 1980. On average, between 1980 and 2009, temperatures passed 50C about 14 days a year.

The number rose to 26 days a year between 2010 and 2019.

In the same period, temperatures of 45C and above occurred on average an extra two weeks a year.

“The increase can be 100% attributed to the burning of fossil fuels,” says Dr Friederike Otto, associate director of the Environmental Change Institute at the University of Oxford.

Why is the BBC now trying to do the work of climate scientists? An analysis like this should be done by experts, who would be aware of all of the problems, uncertainties and limitations of such an exercise. And it should also be properly peer reviewed. The BBC’s Mickey Mouse approach is useful for nothing more than propaganda.

Their own chart, incidentally, shows that there has been no increasing trend since 1998, which rather puts Dr Otto’s unscientific comment in perspective. No proper scientist would make such claims without proof. There is also a clear step up in the data in 1998, which should set alarm bells ringing.

But let’s look at the BBC’s methodology:

Methodology

It went over 50C in my area, why is it not featured?

Reports of record temperatures usually come from measurements taken at an individual weather station, but the data we have studied represents larger areas than those covered by a single station.

For example, Death Valley National Park in southern California is one of the hottest places on Earth. Temperatures in certain parts of the park regularly pass 50C in summer. But when creating an average for maximum temperatures for the wider area, using several different sources, a figure below 50C is reached.

Where is the data from?

The BBC has used the maximum daily temperatures from the high resolution global ERA5 dataset, produced by the Copernicus Climate Change Service. The data is often used to study global climate trends.

ERA5 combines actual weather observations from many sources, such as stations and satellites, with data from modern weather forecasting models.

The process fills in gaps created by poor station coverage in many parts of the world and helps us to understand climate change.

What analysis have we done?

Using the maximum temperature for every day from 1980 to 2020, we identified how often temperatures exceeded 50C.

We counted the number of days and locations with a maximum temperature of 50C or higher for every year, to determine the trend over time.

We also looked at the change in maximum temperatures. We did this by working out the difference between the average maximum temperature over land and sea for the most recent decade (2010-2019) compared with the 30 years before (1980-2009).

Averages of at least 30 consecutive years are known as climatologies. These are used for showing how recent periods compare to a climate average.

What do we mean by ‘location’?

Each location is roughly 25 sq km, or about 27-28 sq km at the equator. These grids can cover large areas and may contain many different types of landscape. The grids are squares of 0.25 degrees latitude by 0.25 degrees longitude.

The key sentence concerns the use of ERA5, which is essentially a computer model. In other words, the BBC is not using actual data at all, merely the outworkings of a model.

Their analysis is only fit for the bin,

Iraq

One of the regions particularly highlighted is Iraq, with the usual tear jerking story:

His tale however does not stand up to scrutiny, as cereal production in Iraq is much higher than it was prior to the turn of the century. Output did drop between 2014 and 2018, but even at its worst, harvests were still much better than in the 1980s, when they supposedly had a nice mild climate.

Although output fell by a half between 2014 and 2015, declines of this proportion have happened before, for instance 1972 to 1973, and 1996 to 2000. These are associated with droughts, not heat.

http://www.fao.org/faostat/en/#compare

New Series

We should not be surprised to learn that the BBC are using this junk science to launch a new series, which doubtless will peddle more lies and misinformation: