| The Iceland Guide | ||
Companion websites The Globe Travel Bookshop The Globe Travel Shop The Globe Travel Guide The Scotland Guide
Books by David Williams |
The land and the people The natural world: The climate Just a casual glance at a climatic map is enough to confirm one surprising fact about Iceland — it is much warmer than its latitude would imply. Cold water drifts south from Greenland, but its effect on the north and east coasts is offset by the passage of the warm Gulf Stream coming from the south-west. The warm current (about 4-12°C) meets the submarine ridge that runs from the Faroes to Greenland and is forced to flow clockwise along the south and west coasts. This keeps the winters less severe than in other countries at the same latitude and while the sea temperature in the north may be about 1°C in February and 7°C in August, the corresponding temperatures in the south may be 6°C and 11°C during the same months. As well as bringing this warm water, the winds from the south–west bring a lot of rain and snow, much of it falling on the southern glaciers. The precipitation on Vatnajökull might be as much as 4,000mm (160 inches) a year, but the ice–cap shelters the highlands to the north and these areas (including Mývatn) might only get 400mm (16 inches) of precipitation each year. Snowstorms however, can occur at any time of the year, as can night frost. Sometimes drift ice may come from Greenland, occasionally managing to get as far as the Westman Islands where it has even blocked Heimaey's harbour. The occurrence of drift ice (which appears first in the north–west) is very serious for, as well as affecting fish shoals and ships, its presence shortens the growing season for the crops, thus cutting the size of the harvest. However, the twentieth century's temperature increase (after the "little ice age" of 1600–1900) has brought about a number of changes in the country. The glaciers have receded between 2–3km and, from 1919–64, there was little sea–ice (although this trend was briefly reversed in the years 1965–68). The growing season has also lengthened. Summer temperatures are now around 9–12°C on average during July, which is generally the warmest month, though the highlands are rather colder with the temperature falling by 0.5–0.7 degrees for each l00m of altitude. Winter temperatures on the coast can be relatively mild, ranging around 2°C–minus 2°C, although in the interior conditions are likely to be much more severe. Towards Greenland and to the north–west of Iceland there is a region of semi–permanent low pressure which makes the country rather windy and its weather changeable, though thunderstorms are rare. Dust storms can occur over the open desert areas on the higher ground, the clouds of dust sometimes reaching l,000m into the air and darkening the sky. In the fjords, sea-mist, brought in by gentle sea breezes, may drift in and blanket the water, settlements and hillsides. There may be strong winds in the area round Akureyri, which lies in a long northerly–facing fjord; these winds start in the afternoon but usually die away after a few hours. Because of Iceland's latitude, the days are very long in the summer and can be exceptionally short during winter. In Reykjavík for example, the longest day is nearly 21 hours long, but the shortest is just under 4 hours. In the north, the summer sun hardly sets at all, with sunset after midnight in July. The amount of sunshine thus varies tremendously through the year; during the years 1931–60, Reykjavík had on average 1,249 hours of sunshine each year, but while there were 189 hours in July, December only enjoyed 8 hours. The country's northerly position also means that the sun never rises more than 50 degrees above the horizon, so the length of the day to the north of hills can be very short, something that was often taken into consideration when settlements were being established. During autumn and the early winter, the "northern lights" (aurora borealis) are often visible, usually as bands of thin coloured rays that lighten the sky, although they can take other forms. The "northern lights" are caused by charged particles from the sun entering the upper atmosphere near the Earth's magnetic pole. Daytime visibility in the summer can be exceptionally good, with mountains visible which are 50–60km away, though perhaps a little hazy. For example, from Reykjavík the Snæfellsjökull glacier, about 110km away to the north–west, can often be seen quite clearly. The lack of industry, together with the change to geothermal energy from peat and coal burning for home heating, means that there is virtually no smoke in the atmosphere, even in the towns. Visibility can be drastically reduced however by low cloud levels when it is raining or by dust storms which can take a long time to die out. In warm weather, persistent heat hazes can reduce visibility and also cause mirages in the form of a "puddle" across the road or the "flooding" of a valley in the distance. |
What`s in the website ? The land and the people History |