Weather describes conditions in the atmosphere that are happening right now. It is the short term occurrence, or daily measurement, of fair or inclement weather. For dealing with weather, daily decisions are necessary. When it is raining, bring an umbrella; when it is stormy outside, take cover inside. Daily temperature, precipitation, and severe weather are all a part of everyday weather. If the meteorologist on TV says that it will be sunny today, this is defined as weather.
Below are pictures describing weather conditions. Figure A is a picture of lightning during a lightning storm. Figure B is a satellite image of Hurricane Ivan as the eye approaches the Florida coast in September 2004.
|Figure A: Cloud-to-Ground Lightning||Figure B: Hurricane Ivan (2004)
|Image from NOAA||Image from NOAA
Climate describes the long-term weather patterns over a specified time frame for a specific area. Most books which describe regional or world climate use a long-term average of weather conditions to describe what typical conditions are likely to be present at a particular location and time of year. The average amount of rainfall is considered a part of climate. Climate statistics include both average conditions and frequencies of occurrence of severe weather, heavy rainfall, and other weather events which could impact health and property.
The latitude of a location has a large impact on the climate for that area. This is primarily due to the amount of solar heating received, which varies as a function of latitude. However, locations with the same latitude may have different climates depending on multiple factors such as whether the location is close to the coast or if the location has significant topographic features, such as a mountain.
Figure C shows annual average precipitation for the US from 1961-1990.
|Figure C: Annual Average Precipitation from 1961-1990.|
Figure D below shows the annual average temperature across the US from 1961-1990.
|Figure D: Annual Average Temperature from 1961-1990.|
Figures E and F show similar conditions as above with emphasis on the southeast US. They show precipitation (in mm) and temperature (in degrees Celsius) averages over a 30-year period.
|Figure E: 30-year Average Precipitation (mm)||Figure F: 30-year Average Temperature (C)|
You can think of differences between weather and climate as similar to differences between people's day to day moods and their personalities. A person is likely to have a consistent personality over time which is described by their long-term behavior regarding talkativeness, optimism or pessimism, and other factors. However, that person may show a lot of variation in their day to day moods, depending on outside influences, state of health, and even how much sleep they receive. Similarly, the climate of a region shows the long-term characteristic behavior of weather over that region. However, the weather on any day can be quite different depending on what weather systems are moving through the area and affecting the day's temperatures, rainfall, and wind conditions.