Polar easterlies
Polar easterlies are cold, dry winds that move outward from polar high-pressure areas toward lower latitudes, blowing from east to west in Earth Science.
What are polar easterlies?
Polar easterlies are the cold surface winds found in Earth Science between the polar high and about 60° latitude. They blow away from the poles, and because of Earth’s rotation, they move from east to west overall, even though the air is actually flowing outward from high pressure toward lower pressure.
The starting point matters. Over the poles, air is very cold, dense, and sinking. That sinking air creates a polar high-pressure system, so the air at the surface spreads outward. As soon as that air moves, the Coriolis effect bends it, so the wind does not travel in a straight line. In the Northern Hemisphere it curves to the right, and in the Southern Hemisphere it curves to the left.
That bending is why the winds are called easterlies. They are named for the direction they come from, not the direction they go. So a polar easterly is a wind coming from the east and moving toward the west, unlike westerlies, which come from the west.
Polar easterlies are part of the polar cell, one of Earth’s three major circulation cells. In the polar cell, cold air sinks at the poles, spreads outward at the surface, and meets warmer air near the polar front around 60° latitude. This boundary is where polar air and midlatitude air interact, which can set up storm systems and shifting weather patterns.
In class, you will usually see polar easterlies on global wind maps, climate diagrams, or circulation models. They help explain why polar regions stay cold and dry, and why the air mass boundaries near 60° latitude matter for weather farther south or north.
Why polar easterlies matter in Earth Science
Polar easterlies show how Earth’s atmosphere moves as a connected system, not as isolated local winds. Once you know where they sit in the global circulation pattern, you can make sense of why polar regions have persistent cold, why pressure belts line up the way they do, and why wind direction changes with latitude.
This term also gives you a clean way to connect three big ideas in Earth Science: pressure differences, the Coriolis effect, and global wind belts. If you can trace air from the polar high to the polar front, you can explain more than just one wind name. You can explain the movement of air masses, the location of climate zones, and the setup for storms near the boundary between cold polar air and warmer midlatitude air.
Polar easterlies also help you read maps and diagrams correctly. If a question asks you to identify a wind belt, explain a climate pattern, or describe why air curves, this term gives you the vocabulary to do it precisely instead of guessing from general weather knowledge.
Keep studying Earth Science Unit 5
Official unit cheatsheet
open one-pagerHow polar easterlies connect across the course
Polar High
Polar easterlies start at the polar high, where cold air sinks and pressure is high near the poles. The sinking air spreads outward at the surface, and that outward flow becomes the wind belt. If you mix up the wind and the pressure system, the whole circulation pattern gets harder to read.
Coriolis Effect
The Coriolis effect bends polar easterlies as they move away from the poles. Without that deflection, the air would travel more directly toward lower pressure. With Earth’s rotation, the path curves, which is why these winds have an east-to-west component instead of moving in a straight line.
Trade Winds
Trade winds and polar easterlies are both easterlies, but they occur in different latitude bands and come from different circulation cells. Trade winds form closer to the tropics, while polar easterlies form near the poles. Comparing them helps you see Earth’s three-cell circulation structure.
polar cell
Polar easterlies are the surface branch of the polar cell. Air sinks over the poles, moves outward near the ground, then rises again near the polar front around 60° latitude. If you understand the polar cell, the wind direction stops looking random and starts making sense as part of a loop.
Are polar easterlies on the Earth Science exam?
A map question might show wind belts and ask you to label the air movement near the poles. That’s when you identify polar easterlies by latitude and direction, not by guessing from the name alone. On a short response, you may need to explain that cold air sinks at the polar high, spreads outward, and is deflected by the Coriolis effect. In a climate or weather analysis, you could use the term to explain why polar regions stay cold and why the boundary near 60° latitude can be a zone of active weather. If you get a diagram, look for the surface winds moving away from the pole and curving because of Earth’s rotation.
Polar easterlies vs Trade Winds
Both are easterly wind belts, which makes them easy to mix up. Trade winds occur between the subtropical highs and the equator, while polar easterlies occur between the polar highs and about 60° latitude. They belong to different circulation cells and affect different climate zones.
Key things to remember about polar easterlies
Polar easterlies are cold surface winds that blow outward from the polar highs and generally move from east to west.
They form because cold, dense air sinks over the poles and spreads toward lower pressure at lower latitudes.
The Coriolis effect bends these winds, so their path curves instead of moving in a straight line.
Polar easterlies are part of the polar cell and are usually found between about 60° latitude and the poles.
On maps and diagrams, look for them as the wind belt near the poles that helps separate polar air from midlatitude air.
Frequently asked questions about polar easterlies
What is polar easterlies in Earth Science?
Polar easterlies are cold winds that blow from the polar high-pressure areas toward lower latitudes. They move from east to west overall and are part of the global atmospheric circulation system. In Earth Science, they help explain why polar regions are cold and how air moves around the planet.
Why are polar easterlies called easterlies?
They are named for the direction they come from, not the direction they travel toward. Polar easterlies come from the east and blow westward. That naming pattern is the same reason trade winds are also called easterlies.
How does the Coriolis effect affect polar easterlies?
As air moves away from the poles, Earth’s rotation deflects it. That makes the wind curve to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. Without that deflection, the flow would be more direct from high pressure to lower pressure.
How are polar easterlies different from trade winds?
Both are easterly wind belts, but they form in different places. Trade winds are in the tropics, while polar easterlies are near the poles between about 60° latitude and 90°. They are part of different circulation cells and influence different climate zones.