Glossary box 1 Arctic Circle Line of latitude at 66 ⁄2°N. North Atlantic Drift A current of warm water, also called the Gulf Stream. It drifts from the Gulf of Mexico across the North Atlantic to the coast of 2a2a A variable climate northern Europe. Three main factors shape the climate of Norway – its northerly position, long coast and mountain ranges. The climate varies across the country. Winter and the North Atlantic Drift Figure A Average January temperatures The nearer an area is to the North or South Pole, the colder it is likely to be. This is because the midday sun is lower in the sky and its rays are less powerful, especially in winter when there are fewer hours of daylight. The further north of the Arctic Circle, the longer daylight disappears during the winter. At Nordkapp (71°N), the most northerly point in mainland Norway, there is almost no daylight from 18 November to 24 January because the sun does not rise above the horizon. In Norway, winter temperatures fall more quickly from west to east (Figure A) than from south to north. Coastal areas are warmed by the sea. Sea water, unlike the land, cools slowly in the winter. The sea is made warmer by the North Atlantic Drift. It comes from the Gulf of Mexico and is moved across the Atlantic Ocean by westerly winds. This current then drifts northwards along the Norwegian coast. The westerly winds passing over it transfer Figure B Ships can the warmth to the land along the coast. The sea off use Tromsø the coast of Norway remains ice-free in winter harbour in winter (Figure B), even north of the Arctic Circle. Eastern Norway is cut off from the warmth along Summer the western coast by mountains. Temperatures are Summer temperatures are more uniform across kept lower by cold air from the Arctic regions. The the country. Though it is cool in the mountains, it is mountains themselves are also cold, because generally warm elsewhere (Figure C), even in the temperatures fall by 1°C for every 150 metres above far north. The days are longer the further north you sea level. go, and north of the Arctic Circle there are 24 hours of daylight in midsummer. This area is known as ‘the land of the midnight sun’ and attracts many tourists (Figure D). Figure C Holiday-makers in southern Norway enjoying the Figure D The midnight sun at Harstad, at bright summer sunshine about 69°N Glossary box Convection rain Rain which falls when land is heated, warming the air above. As the air rises, it cools and releases water droplets. Rain shadow Areas which are on the 2b2b Wetter west, drier east sheltered side of mountains and therefore receive little rain. Rainfall varies considerably across Norway – the west receives Relief rain Rain which falls when far more rain than the drier eastern areas (Figure A). moist air is forced to rise over mountains. Figure A Figure B Annual rainfall Relief rainfall Rainfall Figure D All rainfall is caused by moist In winter, air rising. In Norway, the warm, moist westerly Norway has winds are forced to rise over the mountains which plenty of snow separate western and eastern areas (Figure B). This to attract skiers produces relief rainfall. Eastern Norway is much drier – it is in the rain shadow (Figure C). On hot days in summer, the land in eastern Norway may be heated enough for the air above it to rise and produce convection rain. This rain often falls locally as heavy showers, sometimes with thunder and lightning. Climate and weather Although western Norway has a wet climate, it does enjoy some fine weather. Weather is the day-by-day conditions which may change rapidly. Climate is the average weather recorded over a period of at least 30 years. For example, the climate of Bergen on the west coast is wet, with a lot of rain every month and with the heaviest rainfall in autumn. However, the weather in Bergen can be bright and sunny for many days, especially in the spring. Benefits of a wet climate The wet climate of western Norway does have some benefits. It means heavy snow is likely to fall over the mountains in winter, which attracts winter sports enthusiasts (Figure D). Figure C Flatter land in the county of Akershus in eastern Norway 2c A variable climate 1 On Card 2a, study Figure B and the text. Explain why: a you would expect to find the lowest temperatures in the north of Norway b some of the lowest temperatures are found in the central area between Oslo and Bergen c Bergen is warmer than Oslo in January. 2 Shade Figure 1. Choose colours which suggest warmth, such as pink and red. Use red for the higher temperatures. 3 Look at your map. a What are the warmest and the coolest areas of Figure 1 Average July Norway in July? Give reasons for this. temperatures b If the temperature in Bergen is 15°C, what would you expect the temperature to be in the mountains at the same latitude at a height of 1500 metres? 4 Complete Figure 2 to show the length of day at 6 In groups, discuss the difficulties Tromsø on the first day of each that people might face during the month. Shade the hours of winter in Tromsø. How could they daylight. overcome these difficulties? Do you think the long summer days would 5 How can the presence of snow make up for the dark winters? affect the light conditions in winter? Date Length of day at Tromsø (70°N) Number of hours from sunrise to sunset 1 Jan — 1 Feb 5 1 Mar 9.5 1 Apr 14 1 May 19 1 June 24 1 July 24 Figure 2 Tromsø 1 Aug 21 has midnight sun from 19 May to 22 1 Sep 15.5 July and almost no 1 Oct 11 daylight from 1 Nov 6.5 25 November to 17 January 1 Dec — 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (24-hour clock) 2d Wetter west, drier east Figure 1 Rainfall in southern Norway 1 On Figure 1, add these labels in the correct • Area where relief rain falls places: • Rain shadow area. Norway 2d.1 • North Sea 2a Using the information in the tables, draw rainfall • Bergen, Oslo and temperature graphs for Bergen and Oslo on • Air rising and cooling Figures 2 and 3. Draw a line graph for temperature • Air descending and warming and a bar graph for rainfall. b Explain why: 300 • Bergen has a higher rainfall than Oslo 250 • a relatively high proportion of rain in Oslo falls in 275 the summer months. 225 200 20 20 C ° 175 15 e 15 150 10 atur 10 C ° e 125 5 Rainfall (mm) 5 Rainfall (mm) emper T 100 0 100 0 atur 75 –5 75 –5 emper T 50 50 25 25 J F M A M J J A S O N D J F M A M J J A S O N D Figure 2 Bergen: climate (months) Figure 3 Oslo: climate (months) Bergen: climate Month J F M A M J J A S O N D Temperature (°C) 2 2 3 6 11 14 15 14 12 9 5 3 Annual rainfall: 2250 mm Rainfall (mm) 190 152 170 114 106 132 148 190 283 271 259 235 Oslo: climate Month J F M A M J J A S O N D Temperature (°C) –4 –4 0 5 11 15 16 15 11 6 1 –3 Annual rainfall: 763 mm Rainfall (mm) 49 36 47 41 53 65 81 89 90 84 73 55.