Which part of the world experiences the greatest extremes of temperature?
M Thompson, Coventry
In Verkhoyhansk, Sibera, when it gets hot, it gets pretty hot. But when it gets cold, it gets really cold. Over the course of a year, the temperature in this town in Eastern Yakutia has plummeted to--68[degrees]C and then soared to 35[degrees]C: a difference of 103[degrees]C.
The town is located just inside the Arctic Circle and has a continental climate, being more than 500 kilometres from the northern coast of Siberia. In winter, cold, dry Arctic air helps to cool things even further and this part of Siberia has become known as the Cold Pole. On average, Qimyakon, a village on a plateau to the southeast, is colder, but the two places tied for the lowest temperature recorded outside Antarctica.
Not surprisingly, the White Continent has produced the lowest temperatures ever recorded. The Russian scientific base of Vostock has seen the mercury drop to--89[degrees]C. However, the temperature at the base doesn't even reach as high as--10[degrees]C, so the range there is nothing like that seen in Siberia.
According to James Foster of NASA, the pre-1991 Soviet Union saw the greatest extremes of temperature on the same day, as areas now in Turkmenistan and Uzbekistan could be hot when northern parts of Siberia were registering their lowest temperatures. Post break-up, it's now the USA that is most likely to see huge temperature differences on the same day. Indeed, on 17 August 2002, the USA recorded both that day's highest temperature and its lowest temperature outside Antarctica. The day peaked at 51[degrees]C in Death Valley, California, while a chilly--7[degrees]C was registered in Montana.
Why is Belgium so popular for area comparisons? T Doniher, Scarborough
It's curious how many things have ended up being described as being the size of Belgium. There's a good reason for it: describing things in terms of football fields or the area of a country makes it easier to fix their size in your mind than referring to so many thousand square kilometres.
Like football fields, Belgium has become accepted as a way of conveying the size of large entities. But, Belgium isn't a big country. Today, it covers a total area of 30,528 square kilometres. A circle with a diameter of 196 kilometres--the distance from London to Stafford--would cover the same area.
The world has a total land area of 148,429,000 square kilometres, which is an area of just over 4,862 Belgiums. Brazil, which is currently receiving a lot of the attention, covers an area of 8,511,965 square kilometres, or close to 279 Belgiums. The current extent of the Brazilian rainforest covers an area the size of about 167 Belgiums.
Given the ubiquity of Belgium as a benchmark, the comparisons can sometimes be a little flaky. The 26,000 square kilometres of Brazilian jungle recently chopped down to make way for soybeans was actually some 15 per cent smaller than Belgium: the Republic of Macedonia at 25,333 square kilometres and Albania at 28,748 square kilometres are better matches.
Even research papers succumb to the lure of Belgium. One described the eruption of gases off the coast of Namibia as covering an area two thirds the size of Belgium, which would actually be the area of Wales. For another about societies in the Amazon Basin, the area described as being the size of Belgium covered somewhere between 20,000 and 30,000 square kilometres. So it could have been the size of Wales at the low end. For this kind of area, US citizens often prefer the size of the state of Vermont: splitting the difference nicely at 25,000 square kilometres.
The reason that Belgium turns up so often is down to what psychologists call the'memetic founder effect'. Memes are ideas that people transmit to each other--the conceptual equivalent of genes--and sometimes a meme proves so popular that other, perhaps more accurate or useful memes fall by the wayside. …