Objective: Determine where clouds form using dewpoint and relative humidity Agenda: Cloud Notes Cloudbase lab Wind Notes Isobar practice

1. Condensation surface In order for condensation to occur, two things must take place. The air needs to be saturated. There is a condensation surface available. On the ground, the condensation surface would be the grass. In the air, the condensation surface would be aerosols such as dust, smoke and pollutants.

2. Precipitation This is liquid or solid water that falls from clouds. All clouds are made of tiny water drops or ice crystals. Precipitation happens when the water drops or ice crystal become heavy enough to fall. Precipitation actually cleans the atmosphere by washing the dust, smoke and pollutants back down to the earth. The bad part is that this also causes acid rain

1. There are three main types of clouds. Stratus: horizontally layered clouds Cumulus: puffy clouds Cirrus: feathery clouds

How to determine Dew Point & Humidity Use a sling psychrometer: 1. Find the "dry bulb temp" 2. Subtract the dry and wet bulb. 3. Find the difference on the top Use the exact same procedure for finding the Relative Humidity CHECK YOUR CHART!!

Moving air is called Wind Mt. Washington, NH April 12, World's Strongest Wind:

Wind Basic Rules: 1. Warm air rises 2. There is always air 3. Warm air cools off 4. The Sun heats the GROUND Wind is caused by differences in air pressure

Wind Low Pressure L High Pressure H WIND Wind moves from ________________ to ________________ Remember that...

Wind Which way is it moving??

Wind How about here? ?

Isomaps & Wind Isobars: connect points of equal pressure The closer the lines the higher the wind speed. Think of contour maps made of hills of air...

There is always a more complex map

Weather Instruments Wind Vanes wind direction Thermometers Temperature Barometers Air Pressure Anemometers Wind Speed Leaning Tower of Pisa Mt. Washington -

wind is measured by an anemometer (wind speed) and a wind vane (direction) Wind moves from areas of high pressure to areas of low pressure The Rules of Wind