Richard Tol on UHI

via NOT A LOT OF PEOPLE KNOW THAT
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By Paul Homewood

h/t AC Osborn

Richard Tol has a new paper out about urban warming:

The effects of global warming on cities could be reduced by painting roofs white, a study suggests.

Planting trees, and replacing dark coloured roads and pavements in towns and cities would lower the temperature in towns and and cities by as much as 2°C.

Switching building materials and increasing the amount of plants in our cities could significantly cool them down – making them more pleasant places to be if the earth starts overheating, the study claims.

The effects of global warming on cities could be reduced by painting roofs white, a study suggests. Planting trees, and replacing dark coloured roads and pavements in towns and cities would lower the temperature in towns and and cities by as much as 2C.

The authors of the study, published in Nature Climate change said towns and cities will bear the brunt of global warming, because they are much hotter than the surrounding countryside or sea.

This is because of the ‘urban heat island effect’ – dark, hard surfaces such as black tarmac soak up heat, making the area hotter, while white and lighter coloured ones reflect it away, so less heat is absorbed.

But because cities generate vastly more wealth than the countryside, the impact of global warming will be much more significant unless measures are taken such as greening cities and using surfaces that reflect away heat and light.

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There is nothing new in any of this of course. But what is interesting is this comment:

In the journal Nature Climate Change, the researchers, from Sussex University, Mexico and The Netherlands, wrote: “Between 1950 and 2015, 27 per cent of cities and 65 per cent of the urban population warmed more than the world average (about 0.6C).

“Moreover, during this period, about 60 per cent of the urban population experienced warming twice as large as the world.

In other words, not only is the UHI effect real, it has been increasing since 1950.

Urban and Intermediate stations dominate the GHCN, and there are less rural stations than there were a few decades ago.

It has also been found that most rural stations tend to have short/broken records.

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Berkeley Earth come to similar conclusions, finding that 27% of the Global Historical Climatology Network Monthly stations are located in cities with a population greater than 50000.

Given the domination of urban records, how confident can we be that the effect of UHI is being properly accounted for?