November 11, 2011

Objective:Determine where

clouds form using dewpoint and relative humidity

Agenda:Cloud NotesCloudbase labWind NotesIsobar practice

Cloud Notes

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.

HOW DO CLOUDS FORM AND CAUSE PRECIPITATION?

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

TYPES OF 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 HumidityCHECK YOUR CHART!!

Moving air is called Wind

231mph @ Mt. Washington, NHApril 12, 1934

http://www.mountwashington.org/about/visitor/recordwind.php

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

HWIND

Wind moves from

________________

to

________________

Remem

ber that...

WindWhich way is it moving??

WindHow about here? ?

Isomaps & Wind

Isobars:connect pointsof equal pressureThe closer the linesthe higher the windspeed.

http://ww2010.atmos.uiuc.edu/(Gh)/wx/surface.rxml

Think of contourmaps made of hills of air...

There is always a more complex map

Weather Instruments

Wind Vaneswind

direction

Thermometers

Temperature

BarometersAir

Pressure

AnemometersWind 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