Polar and Highland Climates

Summary

This lecture focuses on polar and highland climates, highlighting the extreme conditions and small population density in these regions. Polar climates, characterized by no true summer, low sun angles, low humidity, and high albedo effects, include tundra, ice caps, and polar marine climates. Tundra climates are cold and covered with snow most of the year, while ice cap climates, found in places like Antarctica, are consistently frozen. Polar marine climates, influenced by oceanic proximity, are slightly more moderate. The impact of climate change on these regions is also touched upon, especially concerning the melting of ice sheets.

Takeaways

• 😀 Polar and highland climates make up only about 2% of the world's population distribution, with extreme conditions.
• 🌍 Polar and highland climates are often grouped together due to similar climatic conditions that arise from both latitude and elevation.
• ❄️ Polar climates have no true summer, and even though summer days can last up to 24 hours, the insolation remains diffuse and the temperature stays very cold.
• 🏔️ Highland climates occur in mountain ranges, where temperature decreases as elevation increases, even near the equator.
• ☀️ Low sun angle and diffuse insolation contribute to the cold conditions in polar and highland climates.
• 🌧️ These areas experience low humidity and low precipitation, making them generally dry regions.
• 🧊 Surface albedo effects in polar regions, caused by ice caps and glaciers, reflect sunlight and contribute to keeping these areas cold.
• 🌍 Climate change is impacting polar regions, particularly through the melting of ice and the increased exposure of dark ocean waters, which alter albedo effects.
• 🏔️ The three key types of polar climates are tundra, ice cap and ice sheet, and polar marine climates.
• 🌡️ Tundra climates are primarily in the northern hemisphere, with land covered in snow for 8-10 months of the year and average temperatures just above freezing during the warmest month.
• 🧊 Ice cap and ice sheet climates occur in extremely cold areas, like Antarctica and Greenland, with temperatures averaging below freezing year-round and experiencing very little precipitation.
• 🌊 Polar marine climates are more moderate than other polar climates due to the influence of nearby oceanic bodies, keeping temperatures above 20°F in winter.

Q & A

What are polar and highland climates, and why are they often considered together?

Polar and highland climates are extreme climates found in very small areas of Earth's surface. They are often considered together because an increase in latitude (moving toward the poles) results in similar climatic conditions as an increase in elevation (moving upward in mountains).

What defines a polar climate, and why is it considered so cold?

A polar climate is characterized by having no true summer and very cold temperatures. Even though some days may have 24-hour sunlight, the sunlight is diffuse, meaning it doesn't provide enough warmth to overcome the cold. This makes it too cold for trees to grow.

How does the temperature change with elevation in highland climates?

In highland climates, the temperature decreases as elevation increases. This means that even in low latitudes, such as near the equator, high mountain ranges can experience cold climates due to their elevation.

What are the three key factors contributing to the cold temperatures in polar and highland climates?

The three key factors are: 1) Low sun angle, resulting in diffuse sunlight; 2) Low humidity and precipitation, making these areas dry; and 3) Surface albedo effects, where ice caps and glaciers reflect sunlight, keeping the areas cold.

What is the role of surface albedo in maintaining the cold temperatures in polar climates?

Surface albedo refers to the reflectivity of Earth's surface. Ice caps and glaciers have a high albedo, meaning they reflect much of the incoming sunlight. This reflection helps maintain the cold temperatures in polar climates, as less sunlight is absorbed by the surface.

How might climate change affect the albedo effect in polar regions?

Climate change may lead to the melting of ice caps and glaciers, which would reduce the surface albedo. As the ice melts, darker surfaces like ocean water or land would be exposed, absorbing more sunlight and potentially warming the area.

What are the three sub-climates of polar climates, and where are they found?

The three sub-climates of polar climates are: 1) Tundra, found in high latitudes or high elevations with long snow cover; 2) Ice cap and ice sheet, located in areas like Antarctica and Greenland, where temperatures are continuously below freezing; and 3) Polar marine, found near the ocean, where maritime influence moderates the cold temperatures.

What are the typical characteristics of a tundra climate?

A tundra climate is characterized by being covered in snow for 8-10 months of the year. The warmest month has an average temperature above zero but never exceeding 10°C, indicating very cold conditions. It is mostly found in the northern hemisphere, with some areas in southern hemisphere mountains and Antarctica.

How does the ice cap climate differ from the tundra climate?

The ice cap climate is even colder than the tundra, with all months averaging below freezing. The ice cap is typically found in places like Antarctica and Greenland, and unlike the tundra, it remains continuously frozen. The north pole's ice cap climate is also extremely dry, unlike the tundra, which can have limited precipitation.

What is the polar marine climate, and how does it differ from other polar climates?

The polar marine climate is a more moderate type of polar climate influenced by oceanic bodies. Unlike the tundra or ice cap climates, it experiences less extreme cold in winter, with temperatures rarely dropping below 20°F. This is due to the moderating effect of the nearby ocean, which keeps temperatures slightly higher than in other polar regions.