Weather+and+Climate.

Weather

__ Origin of the atmosphere __  The early atmosphe ﻿ re very different than today. It was mostly made of water vapor, carbon dioxide, and nitrogen from the out-gassing of volcanoes. All of the water vapor from the volcanoes cooling went into oceans. Carbon dioxide was also produced and used by early organisms that performed photosynthesis. Other percentages of CO2 are tied up in rock deposits like limestone.

__ Why the atmosphere is important today __ The atmosphere holds the oxygen and moderates temperatures on Earth. It provides protection from asteroids, etc. For example think of moon surface and how it is different from the Earth's surface. The atmosphere, specifically the Ozone layer protects us from dangerous forms of electromagnetic energy.

__Air pressure__ is caused by the weight of the atmosphere. It is generally greatest at the surface, and decreases as you gain altitude. A scientist would use a barometer to measure it. Differences in air pressure cause winds. Also, differences in air pressure is the main way to predict weather.

__ Factors that affect air pressure __  • //Altitude//: Air becomes less dense with increasing altitude.  • //Temperature//: Colder air is more dense, therefore it is at a higher air pressure.  • //Humidity//: Usually, air pressure decreases as humidity increases.

__Winds__ are caused by the heat flow through the atmosphere (convection). They are the result of the uneven heating of the earth’s surface. The fastest winds occur when there is a large gradient (change) in pressure over a small distanc

__ Local winds: __ A Land breeze is a wind that blows from the land towards the sea. A sea breeze is a wind that blows from the sea towards the land, usually occurs during the afternoon as land heats up.

The coriolis effect  • Apparent curvature of winds (or ocean currents etc.) over long distances along the earth’s surface. <span style="font-family: Verdana,Geneva,sans-serif;"> • Due to the rotation of the earth. <span style="font-family: Verdana,Geneva,sans-serif;"> • In the northern hemisphere, winds curve to the RIGHT. <span style="font-family: Verdana,Geneva,sans-serif;"> • Southern hemisphere is opposite. <span style="color: windowtext; font-family: Verdana,Geneva,sans-serif; font-size: 19px;">Jet streams <span style="font-family: Verdana,Geneva,sans-serif;"> • Very fast currents of air in the upper atmosphere. <span style="font-family: Verdana,Geneva,sans-serif;"> • Where we live, the jet stream flows from west to east. <span style="font-family: Verdana,Geneva,sans-serif;"> • This knowledge helps us to predict weather. <span style="font-family: Verdana,Geneva,sans-serif;"> • Meaning, we will most likely experience the weather that is to the west of us. <span style="color: windowtext; font-family: Verdana,Geneva,sans-serif; font-size: 19px;">Recap

<span style="color: windowtext; font-family: Verdana,Geneva,sans-serif; font-size: 19px;">Be able to discuss the following: <span style="font-family: Verdana,Geneva,sans-serif;"> • How did the atmosphere form, and what is its current structure? <span style="font-family: Verdana,Geneva,sans-serif;"> • What is air pressure? <span style="font-family: Verdana,Geneva,sans-serif;"> • What are winds and what causes the strongest winds? <span style="font-family: Verdana,Geneva,sans-serif;"> • What is the coriolis effect? <span style="font-family: Verdana,Geneva,sans-serif; font-size: 21px;">Weather Systems

<span style="font-family: Verdana,Geneva,sans-serif; font-size: 21px;">How does energy enter the atmosphere? <span style="font-family: Verdana,Geneva,sans-serif;">• The Sun is the major source of energy for the Earth. <span style="font-family: Verdana,Geneva,sans-serif;">• Stars (like our Sun) give off electromagnetic energy, can you list any forms of electromagnetic energy? <span style="font-family: Verdana,Geneva,sans-serif;">• Chart of the electromagnetic spectrum can be found on print page 14 of your ESRT. <span style="font-family: Verdana,Geneva,sans-serif; font-size: 21px;">The states of water <span style="font-family: Verdana,Geneva,sans-serif;">• Solid, liquid and gas. <span style="font-family: Verdana,Geneva,sans-serif;">• Heat is measured in calories. <span style="font-family: Verdana,Geneva,sans-serif;">• Temperature is the measure of the average kinetic energy of the atoms in a substance. <span style="font-family: Verdana,Geneva,sans-serif;">• Melting and vaporization-energy is absorbed. <span style="font-family: Verdana,Geneva,sans-serif;">• Freezing and solidification-energy is released. <span style="color: #ccccff; font-family: Verdana,Geneva,sans-serif; font-size: 21px;">[|Synoptic Weather Map] <span style="font-family: Verdana,Geneva,sans-serif;">Shows a variety of atmospheric quantities such as temperature, air pressure, or specific weather conditions. <span style="font-family: Verdana,Geneva,sans-serif;">• Synopsis (definition)= general summary. <span style="font-family: Verdana,Geneva,sans-serif;">• Because weather generally moves from west to east, these maps can be used to make predictions about future weather. <span style="font-family: Verdana,Geneva,sans-serif; font-size: 21px;">Air Masses <span style="font-family: Verdana,Geneva,sans-serif;">• Large parcels of air that have a uniform temperature, pressure and humidity. <span style="font-family: Verdana,Geneva,sans-serif;">• Leading edge of the air mass is called a //front.// <span style="font-family: Verdana,Geneva,sans-serif;">• The characteristics of an air mass depends on it’s geographic origin. <span style="font-family: Verdana,Geneva,sans-serif; font-size: 21px;">Types of air masses <span style="font-family: Verdana,Geneva,sans-serif;">• cA-continental artic, very cold and very dry <span style="font-family: Verdana,Geneva,sans-serif;">• cP-continental polar, cold and dry <span style="font-family: Verdana,Geneva,sans-serif;">• cT-continental tropical, dry and warm <span style="font-family: Verdana,Geneva,sans-serif;">• mT-maritime tropical, warm and moist <span style="font-family: Verdana,Geneva,sans-serif;">• mP-maritime polar, cold and moist <span style="font-family: Verdana,Geneva,sans-serif;">• In general, maritime=humid and continental=dry <span style="font-family: Verdana,Geneva,sans-serif; font-size: 21px;">Weather systems/high pressure <span style="font-family: Verdana,Geneva,sans-serif;">• Represented by a large “H” on weather map. <span style="font-family: Verdana,Geneva,sans-serif;">• High pressure brings dry and cooler weather. <span style="font-family: Verdana,Geneva,sans-serif;">• Circulate clockwise and outward, air is sinking. <span style="font-family: Verdana,Geneva,sans-serif;">• Also known as an //anticyclone.//

<span style="font-family: Verdana,Geneva,sans-serif; font-size: 21px;">Weather Systems/ Low pressure <span style="font-family: Verdana,Geneva,sans-serif;">• Represented by a large “L” on map. <span style="font-family: Verdana,Geneva,sans-serif;">• Associated with poor or stormy weather. <span style="font-family: Verdana,Geneva,sans-serif;">• Air rises and moves inward, while circulating counterclockwise. <span style="font-family: Verdana,Geneva,sans-serif;">• Also known as a cyclone. <span style="font-family: Verdana,Geneva,sans-serif;">• Causes cloudy, rainy or changing conditions.


 * <span style="font-family: Verdana,Geneva,sans-serif;">[|water cycle] ||  ||   ||   ||   ||
 * <span style="font-family: Verdana,Geneva,sans-serif;">The Earths [|water] ||  ||   ||   ||   ||