If It Looks Like UHI, Heats Like UHI, And Graphs Like UHI, Then It Probably Is UHI

by Guido Guidi and Maurizio Morabito

Our friend Teo has just expressed his personal and perfectly reasonable opinions about new, old publishing venture called “Wiley Interdisciplinary Reviews: Climate Change (WIRCC)“.

In fact, we find it hard to disagree with him.

The subject of Urban Heat Islands (UHI) is topical, and it is somewhat ironic that such a self-evident effect is so happily dismissed away by AGW proponents. One suspects UHI is extremely inconvenient and uncomfortable to consider to those strictly supporting only the greenhouse-gas-emission side of AGW theory.

Who them? By sheer coincidence, only the greenhouse-gas-emission side of AGW theory can be used to dictate deep societal changes. But that’s another story.

Let’s just add some considerations based on a Willis Eschenbach post on WUWT. It’s a simple but eloquent analysis of a dataset of temperatures, with measures coming from about seventy stations over Northern Europe. Interestingly, an analysis of the monthly data across the decades for the duration of the dataset, shows a warming trend to be occurring primarily in winter months.

NORDKLIM Decadal monthly temperatures, 1900-1999

And what kind of forcing is especially important in the coldest period of the year? No prize for guessing that one right. This is precisely what is expected from the UHI effect, and it is due to changes over time to the environment surrounding the measurement equipments. Roads, buildings, infrastructure are built, woods are fallen and so on. That’s “Anthropogenic” as well, of course, and it has all the potential for local and global consequences.

Data so heavily biased are simply not compatible with the currently fashionable “globalization of forcing“, the mistaken belief that temperatures overwhelmingly taken on land and in heavily urbanized areas, are representative of the thermal state of the entire Blue Planet.

Think of it for a minute. We are talking about temperature anomalies with a positive trend coming from winter months. We are talking of continental regions at high latitudes. We are talking about winters with little insolation, in areas with a high albedo (reflecting visible light!) due to large amounts of snow cover.

• Temperature sensors, under those specific conditions, show a gradual Winter warming

In the summer, with a much lower visible-light albedo in the absence of snow, the incoming solar radiation is absorbed and then re-emitted as longer waves: exactly those “captured” by greenhouse gases.

• Temperature sensors, despite the abundance of infrared radiation, show no Summer warming

How could the positive anomalies be ascribed to a greenhouse effect, that remains a mystery to us. It definitely looks like this is enough to ring more than a few alarm bells, no matter what has been said in the past and by whom.

And the problem of telling between the greenhouse gas contribution to warming, and all other anthropogenic and natural effects, does not just apply to urban setting. It remains to be seen about who’s going to care about it, bringing forward a better understanding of the climate, rather than continuing to run like headless chicken always after the next CO2 molecule, as if it were volcanic ash…