Climate Change · Part One
Climate Change 1 Syllabus
1.0 - Introduction
2.0 - The Earth's Natural Greenhouse Effect
3.0 - The Greenhouse Gases
4.0 - CO2 Emissions
5.0 - The Earth's Carbon Reservoirs
6.0 - Carbon Cycling: Some Examples
7.0 - Climate and Weather
8.0 - Global Wind Systems
9.0 - Clouds, Storms and Climates
10.0 Global Ocean Circulation
· 10.1 - Ocean Circulation & Climate
· 10.2 - Strawberries in Norway
· 10.3 - The Icelandic Whirlpool
· 10.4 - Origin of the Gulf Stream
· 10.5 - The Deep Atlantic Conveyor
11.0 - El Niño and the Southern Oscillation
12.0 - Outlook for the Future
Climate Change · Part Two
Introduction to Astronomy
Life in the Universe
Glossary: Climate Change
Glossary: Life in Universe
Strawberries in Norway
Map of the North Atlantic Ocean showing the Gulf Stream and the North Atlantic Current (Represented by the thick black lines). See other image for greater detail of the currents directly off the Norwegian coast. Cold currents originating in the north are represented by short-dashed lines. Note how some of the water gets recirculated into the North Atlantic subtropical gyre.
Differing Climates of Norway and Greenland
Ocean currents play an important role in transferring heat from the warm tropics to the cold polar regions. An example is the relatively mild climate of Norway that depends upon the warm waters brought north along the Norwegian coast through an extension of the Gulf Stream System.
In Norway strawberries are called "earth-berries", and one can buy them from fruit stands along the road, when in season. We must remember that Oslo, the capital of Norway, is at 60°N, and that more than eighty percent of Norway is north of Oslo, between 60 and 70°N. By contrast, to the west across the Nordic Sea, there is Greenland: an island almost entirely covered by thick ice sheets. Its southern tip is also at 60°N here glaciers reach sea level and produce the icebergs which drift away into the North Atlantic threatening the safety of ships. There are no plants of any kind and certainly no strawberries. Halfway between Norway and southern Greenland lies Iceland with its impressive glaciers, some of which reach down to sea level. However, Iceland is quite green, with plenty of grazing for sheep (providing wool for the splendid Icelandic sweaters).
Why the island covered with ice is called Greenland and the one that has pastures is called Iceland has to do with real estate speculation in Viking times, and need not concern us further. But we do have to ask, why are Norway and Iceland so entirely different from southern Greenland (which is, after all, situated in the same latitudinal belt of 60 to 70°N)? How can we have a modern bustling city with a well-attended university in Tromsoe, Norway right at 70°N? In same latitude in North America we find ourselves at the Arctic shores of Alaska and Canada, and in Greenland we are on top of an immense ice sheet. In Asia, at 70°N, we are in the northernmost tundra of Siberia, in regions where the ground is always frozen (a phenomenon known as "permafrost").
The Gulf Stream: Norway’s Heating System
What is it then that makes Norway so special? The answer is found in the heat transferred by ocean currents and southwesterly winds to the shores and coastal ranges of Norway. Warm waters, heated by the Sun in the subtropics, feed the majestic Gulf Stream, which meanders north off the East Coast to turn east off Newfoundland. The North Atlantic Current then warms the shores of the British Isles and all of northwestern Europe. A portion of this current finds its way up to Iceland and on into the Norwegian Sea. A (relatively) warm current flows all the way up to Tromsoe and beyond, bringing heat into the Barents Sea and even to the shores of Spitsbergen. Thus, Norway has a special heating system, with its origin all the way in the Caribbean!
Map of the Norwegian Sea with its complicated currents. Colored arrows are surface currents and black arrows are deep water currents. Red arrows are “warm” currents originating at the lower latitudes, and blue arrows are “cold” currents originating at higher latitudes. Notice how warm waters tens to found close to Norway, while colder waters are found off of the coast of Greenland.