05. Air Pressure & Wind

Find out how air pressure is represented by isobars:

• http://weather.about.com/od/i/g/isobars.htm

• http://www.weatheronline.co.uk/reports/wxfacts/Isobars-on-surface-maps.htm

• http://www.windfinder.com/forecasts/wind_indonesia_akt.htm

Identify the various weather instruments to measure wind such as windsock, anemometer, wind vane and aneroid baraometer.

Check out the animation on the following website:

http://www.classzone.com/books/earth_science/terc/content/visualizations/es1903/es1903page01.cfm?chapter_no=visualization

Try out this exercise on the use of a barometer. Enter the readings on the barometer - Setting hand (movable pointer) is in blue and the Measuring hand is in red.

Then indicate whether it shows that the atmospheric pressure is increasing or decreasing.

Source: http://www.ontrack-media.net/gateway/science8/g_s8m0l7s6.html

The wind direction is recorded on a wind rose. The prevailing wind is the wind direction with the most number of winds blowing from.

The number in the centre shows the number of calm day

.

When there is a difference in air pressure, air will move from an area with higher air pressure to an area with low air pressure. This will results in the formation of wind.

Local wind system - Land and sea breeze

Learn how to draw an annotated diagram of how sea and land breeze are formed.

Monsoon are seasonal winds on a regional scale.

India experiencing SW Monsoon in July which brings heavy rain as the onshore wind crosses the Indian ocean.

The NE Monsoon is an offshore wind for India and bring little or no rain to India.

Regional wind system - Monsoon (NE and SW Monsoon for India and Malaysia) @https://sites.google.com/a/moe.edu.sg/sec3geog/weather-and-climate/wc-k1-lesson-6