Transcript Day 46
Day 46 Investigation 9 part 1 Air Masses Earth’s Weather • Earth’s weather happen where? Troposphere Greatest variation in temperature, humidity and pressure 10 to 24 km (6 to 15 miles) thick Troposphere Closest to Earth's surface Contains dust, water vapor, and clouds Densest layer, 80% of atmosphere mass Stagnant Air • An air mass that stays over a portion of Earth’s surface for a long time and doesn’t move • Can form over any part of the Earth – Usually forms over areas with uniform surfaces with few mountains – Called source regions • Stagnant air changes, depending upon the type of surface below the air Large bodies of air that stagnant over Earth’s surface Air Masses Large thick bodies of air that are uniform in temperature and humidity Characteristics Large Hundreds of miles across Thick Extend into the troposphere 6 to 8 miles Uniform Same temperature and humidity North American Air Masses • Location B (northern Canada) • Characteristics of the Air? – Cold – Dry North American Air Masses • Location D (Gulf of Mexico) • Characteristics of the Air? – Warm – Humid North American Air Masses • Meteorologists use a code when making notes about the air masses • Combine the names of air masses – Continental (c) - land – Maritime (m) - ocean or sea – Polar (P) - near the poles – Tropical (T) - tropical North American Air Masses • Location B – Located over Canada – Continental polar air mass • Continental Polar – Air mass that forms over cold land • Location D – Located in the Gulf of Mexico – Maritime tropical air mass • Maritime Tropical – Air mass that forms over warm water • Maritime - anything to do with oceans or seas North American Air Masses Determine the air mass code for each air mass Don’t forget: Lower case term will go first !!!! North American Air Masses mP cP mP cT mT mT Air Masses Formation Air is moving Does not stagnate Does not pick up the characteristics from the surface below No Air Masses are formed here Air Masses Formation Coldest air masses form here in the winter Called the Horse Latitudes Warmest air masses form here in the summer Balloon Demo. • Let’s take the large plastic bag outside to see if we can create an air mass. • How might we accomplish this? Solar Balloon Demonstration • Take page 55 of of your lab book. • Answer questions 1-4 after the demonstration. Solar Balloon Discussion • Why is the bag starting to float? • What is happening to the temperature and density of the air inside the bag? • What is happening to the plastic bag itself? Describe any changes you observe.