Wind and Weather: Core Concepts

Begin to Understand All Weather by Knowing These 3 Basics

The three processes on this page explain all weather.  The rest is details. Understanding the wind and the waves it creates are essential to competitive paddling. This module will teach the very basics of weather.

The science of weather is complex and deep.  HOWEVER, to us laymen, understanding a few basic objects of weather can assist in a basic understanding of whats going on.

We will explore the very simple basics of: air masses, the fronts that form the boundaries between them, the weather they create and how that affects wind strength and direction. If you wish to understand more about weather, wind and waves, a much more detailed module on the various aspects of each of these is available on this site.

1   Sun Shine

All of the energy affecting the earth is thought to originate from the sun.  Most certainly the basics of weather is the sun heats the earth and the atmosphere. The earth revolves with the sun almost directly overhead the equator. This is the origin of Air Masses. Bodies of air with similar temperature and moisture content.

The atmosphere is therefore heated unevenly. As air rises when heated, the warm atmosphere has buoyancy and  rises. Cooler air moves in to the void.

Another basic concept of understanding weather is that of relative motion.

2   Wind

The sun heats the earth.  The air above it is warmed, becomes more bouyant and rises.

This rising air is replaced by lateral movement of cooler air, which is less bouyant.

This movement of air we call wind. The movement of air and its interaction is the basis of ALL weather.

3   Coriolis Force

Coriolis Force is an effect that occurs when the earth rotates underneath something that is moving across its surface.  To easily understand this, picture yourself walking sideways across one of those airport moving sidewalks.  Your destination is straight ahead of you, however as the sidewalk moves along your landing spot is different than your trajectory.  It is the same with the earth.  As the earth moves underneath the wind (for example) the trajectory of the wind will be deflected relative to the earth.

See the illustration. In the inertial frame of reference (upper part of the picture), the black object moves in a straight line. However, the observer (red dot) who is standing in the rotating frame of reference (lower part of the picture) sees the object as following a curved path.

This means the wind blows perpendicular (at 90 degrees) to where it is going.

The "rule of thumb" is that in the Northern Hemisphere, wind and currents are deflected toward the right; in the Southern Hemisphere they are deflected to the left

Understanding these simple basics can help understand much of the complexities of weather. Next, read about the details in Air Masses and Fronts.

Credit Where Credit is Due

The source of some of the material that follows in the Wind Module is the COMET® Website at http://meted.ucar.edu/ of the University Corporation for Atmospheric Research (UCAR)), sponsored in part through cooperative agreement(s) with the National Oceanic and Atmospheric Administration (NOAA), U.S. Department of Commerce (DOC) ©1997-2009 University Corporation for Atmospheric Research. All Rights Reserved.

Much of the narrative is my own gained from a lifetime in aviation, numerous courses in meteorology and more than 10 years of paddling the waters of coastal Canada.