Week 8 Notes • Tonight • Weather Review • Term Paper Outline Guidelines • AMS Climate Change Policy (HW#6) • Airmasses and Fronts (Chp 8) • El Niño Classwork (HW#7) • El Niño and La Niña • March 24 – No Class (Spring Break) • March 31 – No Class (Cesar Chavez Day)
Week 8 Notes (cont’d) • April 7 • Remote Sensing • Weather Forecasting • Review for Midterm #2 • April 14 • Midterm #2 • Term paper Outlines Due • April 21 • Thunderstorms and Tornadoes
Due Apr 14 • Typed • Double Spaced • Formatted per next page • References • At Least 3 references • You can add more references later • Only 1/3 Internet only sources • Proper formatting for electronic sources • APA Format only (link in Syllabus) Term Paper Outline
I. Introduction • II. Three Major Points • A. Point 1. • 1. Subpoint 1 • 2. Subpoint 2 • B. Point 2. • 1. Subpoint 1 • 2. Subpoint • C. Point 3. • 1. Subpoint 1 • 2. Subpoint 2 • III. Summary • References: • At Least 3 references • APA Format only (link in Syllabus) • Only 1/3 Internet Sources (and properly formatted) Term Paper Outline
I. Introduction • A. Performed by Committee of Citizens named by Board of Educ. • B. Findings: • 1. Unsatisfactory sports facilities • 2. Ongoing traffic and parking congestion. • 3. Outdated science labs • 4. Outdated physical facilities: • II. Funding Sources: • A. Bond referendum passed by votes of four sending towns on 12/9/03. • B. Breakdown: • 1. $8.8 million provided by communities via increased taxes. • 2. $6.3 million provided by State of NJ via school funding pool. • C. Timetable for Expenditures: • III. Benefits to School and District: • A. Reduction of Special Education costs by keeping students at school. • B. Maintenance of Property values for sending district real estate. • C. Enhancement of education program at the school. • IV. Drawbacks to School and District: • A. Increased property taxes to residents for 15-20 years to pay off bond. • B. Disruption of academic programs at Gateway during the period of construction. • C. Re-location of sporting events and some programs during renovations. • V. Conclusion: Although there will be some costs involved and some disruption, believe the benefits of renovating Gateway H.S., with substantial funding from the State of N.J., are in the best interests of all students and residents. Sample Term Paper Outline
CLIMATE CHANGE POLICY • IPCC - Intergovernmental Panel on Climate Change • Set up by World Meteorological Organization (WMO) • IPCC Fourth Assessment Report 2007 • 1000+ Scientists • Synthesis of Exisitng Research • No Actual research or Data Collection • AMS – American Meteorological Society
AMS CLIMATE CHANGE POLICY - HW#6 • Divide into SIX GROUPS • Read individually your section • Discuss as a group • Come up with at least one “bullet point” per paragraph • Choose a group spokesperson who will present to the class • Each group will turn in a sheet of paper with members names CLEARLY WRITTEN • Group: • #1 – Background • #2 – How is Climate Changing? • #3 – Why is Climate Changing? • #4 – How Can Climate Change be Projected in the Future? • #5 – How will Climate Change in the Future? (First 4 paras) • #6 – How will Climate Change in the Future? (Last 4 paras)
Air Mass Development Semi-permanent circulation patterns provide consistent wind patterns and breeding grounds for air masses.
Air Mass Properties • Take on the properties of the underlying surface • Characterized by Temperature and Humidity • Classified by location of “origin” • Geographically • Tropical • Polar • Arctic • Surface Properties • Maritime • continental • Characteristics more prevalent if air mass remains over source region for a long period
Air Mass Classifications • cP - continental Polar • Cold, dry, stable • Extremely cold cP air mass may be designated cA (continental Arctic) • mP - maritime Polar • Cool, moist, unstable • mT - maritime Tropical • Warm, moist, usually unstable • cT - continental Tropical • Hot, dry • Stable air aloft, unstable surface air • cA – continental Arctic
Continental Polar (cP) • Cold, Dry • Develops over the interior of • North America -- Central Canada -- Siberia Arctic Air (cA) • Bitterly Cold and Very Dry • Develops over the snow or ice usually north of 60° N
Marine Polar (mP) • Cold, Moist • Source: Cold ocean waters of the North Pacific and North Atlantic • Often conversion of cP Siberian air to mP which is moistened and warmed from the Japanese “Gulf Stream Current” • Major type for storms to affect N. California and the Pacific NW • Responsible for fueling “Nor-easters”
Tropical (T) • Continental Tropical (cT) • Hot, Dry • Source: Deserts of Mexico and the SW United States • Very unstable because of heat and convection, but cloudless because of lack of moisture. • Marine Tropical (mT) • Warm, Humid • Source: Tropical and subtropical oceans and the Gulf of Mexico
Example Air Masses cP mT
Air Mass Modification • Air masses eventually move • If it moves over a region different from where it originated, the air mass will be modified, by the land that the air is travelling over. • Changes: warming, cooling, adding or reducing moisture content
Air Mass Modification cP The cP air mass will be warmed by the warmer land that it passes over. Warmer Land
Air Mass Modification mP cP • Originates as cP air from Asia and is carried across the Pacific becoming mP
Fronts • Fronts • Narrow transition zone between air masses of differing densities. • The density differences usually arise from temperature differences. • Density differences may be a result of humidity differences (summer). • A front is the boundary or transition zone between different air masses.
Cold Front • Cold Front • Boundary with a colder (more dense) airmass advances and displaces the warmer (less dense) air. • The largest temperature differences are normally associated with cold fronts. • Average speed ≈ 30 mph • Temperatures drop rapidly
Cold Front • Precipitation: Located on either side of the front. • Convective, showery in nature
Warm Front • Warm Front • Colder (more dense) air retreats and is replaced by the warmer (less dense) air. • Warm fronts tend to have weaker temperature gradients. • Average speed ≈ 16 mph • Temperatures slowly rise
Warm Front • Lifted warm air produces widespread clouds and precipitation well in advance of boundary
Occluded Front • Cold fronts typically move faster than warm fronts. • Cold fronts can catch up and “overtake” a warm front. • Two types of occlusions: • Cold type occlusion • Warm type occlusion (very, very rare)
What kind of front is it? • From the vantage point of the ground… • If warm air replaces colder air, the front is a warm front • If cold air replaces warmer air, the front is a cold front • If the front does not move, it is a stationary front • Occluded fronts do not intersect the ground; the interface between the air masses is aloft
Convergence and Divergence Low High What initiates “cyclogenesis?” When upper-level divergence is stronger than lower-level convergence, more air is taken out at the top than is brought in at the bottom. Surface pressure drops, and the low intensifies, or “deepens.” 500 mb height
Generation of Divergence Aloft UPPER LEVEL DIVERGENCE INITIATES AND MAINTAINS A SURFACE LOW.
Formation of Cyclones • Cyclogenesis – Development of a region of low pressure -- a cyclone. • Conditions: • Cyclonic flow must be established at the surface. • Cyclonic flow is CCW in the Northern Hemisphere. • Convergence at the surface must be supported by divergence aloft.
Wave Cyclone Development cP Cloud “Shield” The cyclone matures “Comma” shape is characteristic of a well developed wave cyclone. L mT
Wave Cyclone Development The cyclone occludes Cold front overtakes warm front. The cold air surrounds the cyclone. Gradients weaken and the low slowly dies. L cP mT