Unit 4 Weather and Climate

Unit 4 Weather and Climate

What is the difference between ‘weather’ and ‘climate’?

Weather: The state of the atmosphere at a given <me and place, with respect to variables such as Temp, Moisture, Wind Air pressure

Copyright © 2010 Ryan P. Murphy

Climate: The average weather of a par<cular part of the world at different <mes of the year.


Weather and Climate are Related

Where is this?

Camping on deposi<onal sand bars

Petroglyphs are carvings that are incised, abraded or ground by means of stone tools upon cliff walls, boulders and flat bedrock

surfaces.

Can you spot the wildlife?

HI Capacity or high Competence?

What helps explains the transi<on from interior dry-‐lands to coastal

rainforest?

Mountains, “Rain-‐shadows” and “Orographic” Rainfall

World Climate Zones

Tropical Climates Tropical moist climates extend north and south from the equator to about 15° to 25° latitude. In these climates all months have average temperatures greater than 64°F (18°C) and annual precipitation greater than 59".

Dry Climates Loss of water exceeds precipitation. These climates extend from 20°-35° North and South of the equator and in large continental regions of the mid-latitudes often surrounded by mountains.

Arid Environments

Evaporation is the process by which water changes from a liquid to a gas or vapor. Transpiration evaporation of water through minute pores, or stomata, in the leaves of plants.

Semi Arid Environments

Temperate. In this zone, there are typically warm and humid summers with thunderstorms and mild winters.

Continental. These regions have warm to cool summers and very cold winters. In the winter, this zone can experience snowstorms, strong winds, and very cold temperatures—sometimes falling below -22°F (-30°C)!

Polar Climates Polar climates have year-round cold temperatures with the warmest month less than 50°F (10°C). Polar climates are found on the northern coastal areas of North America, Europe, Asia, and on the land masses of Greenland and Antarctica.

What factors affect weather and climate?

(1) Atmosphere – our focus for today, however… (2) The Water Cycle (3) The Sun (4) The Ocean

(1) The Atmosphere: A star<ng point – comes from Greek “atmos” meaning vapour and “Sphairia” meaning ball

Our atmosphere is composed of 78% nitrogen and 21% oxygen; the rest is made up of small amounts

of trace gases.

•  This thin layer is our atmosphere.

Importance of the atmosphere….


1.  Keeps planet warm – via the Greenhouse Effect –

-‐ Heat is trapped close to the surface of the Earth by “greenhouse gases ” carbon dioxide, methane and nitrous oxides. -‐ Like a blanket wrapped around the Earth, which keeps it toas<er than it would be without them.


Greenhouse effect also means we find water in all three states..


•  The Moon does not have an atmosphere and is extremely cold in the shade, and extremely hot in the sun.

2. Provides oxygen to breathe


3. Protects us from small meteors.


•  4. Has ozone that protects us from radia<on (UV).


•  Title: Layers of the Atmosphere

Layers determined by temperature

Troposphere •  Weather occurs here •  Life occurs here •  0-‐12 Km

Stratosphere Located above the troposphere and below the mesosphere: 12-‐50 km -‐ Air planes fly here •  Contains “good ozone” layer •  The ozone layer helps protect us from ultraviolet radia<on (UV) from the sun

Mesosphere •  The mesosphere starts just above the stratosphere and extends to 85 kilometers (53 miles) high. Meteors burn up in this layer

Thermosphere •  The thermosphere starts just above the mesosphere and extends to 600 kilometers (372 miles) high. Aurora and satellites occur in this layer.

Exosphere •  This is the upper limit of our atmosphere. It extends from the top of the thermosphere up to 10,000 km (6,200 mi).

Atmospheric pollu<on

Air Pollu<on can be….

Global

a)Global Warming = Climate Change

•  hips://www.youtube.com/watch?v=oJAbATJCugs

b) Ozone Deple<on Ozone is important! •  absorbs most of the UV radia<on from sun. •  Life as we know it wouldn’t be possible without this layer of protec<on.

•  hips://ozonewatch.gsfc.nasa.gov/ozone_maps/movies/OZONE_D1979-‐11%25P1Y_G%5e1920X1080.IOMPS_PNPP_V21_MMERRA2_LSH.mp4

•  Thinning rather than an “hole” •  The regula<on of chemicals has helped

•  hips://www.youtube.com/watch?v=aU6pxSNDPhs&t=7s

Depletion of the Ozone layer vs Climate Change These two issues can become very confused in some people’s minds.

Depletion of ozone layer (ozone hole) •  The ozone layer is in the stratosphere. •  This ozone is created when high-energy

UV strikes an oxygen molecule – a natural process.

•  Ozone protects us from UV radiation •  Depletion of ozone (the ozone hole) was

caused by long-living chemicals, CFCs, that humans released into the atmosphere.

•  International agreements such as the Montreal Protocol have banned the use of CFCs.

•  There is a good chance that the ozone hole will mend in the near future

•  This is a relatively straightforward issue

Climate Change (CC) or Global warming •  Greenhouse gases (GHG) e.g. CO2 are found in

the troposphere. •  GHGs are important for keeping Earth warm

because they form an invisible layer that traps heat that is radiating away from Earth.

•  But extra GHGs are accumulating in the atmosphere because of human activity.

•  So extra heat is being trapped, warming the surface of the Earth.

•  The climate system is affected by many factors which makes the issue very complex e.g. the Earth is warming but some parts are getting colder

•  CC can not be easily fixed.

Climate Change and Ozone Deple<on

•  Read the webpage on Ozone Deple<on and Climate Change and answer the ques<ons posted to our website.

•  hips://www.canada.ca/en/environment-‐climate-‐change/services/air-‐pollu<on/issues/ozone-‐layer/deple<on-‐climate-‐change.html

•  hips://www.youtube.com/watch?v=08z_xW-‐szwM

Focus Ques<on •  Climate change is a complex problem. But we’ve successfully

addressed environmental problems before. Ozone deple<on is an example. When watching the video think about this:

•  What can we learn from the story of ozone deple<on that might help to address climate change?

•  Write down some ideas from the video.

•  hips://www.youtube.com/watch?v=08z_xW-‐szwM

Regional Air Pollu<on: Acid rain •  hips://www.youtube.com/watch?v=1PDjVDIrFec&t=4s

Regional – read and explain to your partner….

Acid rain -results when sulfur dioxide (SO2) and nitrogen oxides (NOX) are emitted into the atmosphere and transported by wind and air currents. SO2 and NOX react with water, oxygen and other chemicals to form sulfuric and nitric acids. These mix with water and other materials before falling to the ground Major sources of SO2 and NOX in the atmosphere are: 1) Burning of fossil fuels to generate electricity. Two thirds of SO2 and one fourth of NOX in the atmosphere come from electric power generators. 2) Vehicles and heavy equipment. 3) Manufacturing, oil refineries and other industries. Winds can blow SO2 and NOX over long distances and across borders making acid rain a problem for everyone and not just those who live close to these sources. .

Local Air Pollu<on: Smog and Urban Heat Islands

Smog over Shanghai Towers, China

Smog, Los Angles

Smog, Cairo

https://www.youtube.com/watch?v=CdbBwIgq4rs

Lets take a test….

•  hips://ed.ted.com/lessons/the-‐science-‐of-‐smog-‐kim-‐preshoff/review_open#ques<on-‐1

Smog is ground level ozone – or bad ozone.

Produced when sunlight reacts with nitrogen oxides and at least one volatile organic compound (VOC) in the atmosphere. Nitrogen oxides come from car exhaust, coal power plants, and factory emissions. VOCs are released from gasoline, paints, and many cleaning solvents. When sunlight hits these chemicals, they form airborne particles and ground-level ozone—or smog.

Reducing Smog: What can you do? •  Drive less. •  Take care of cars. Gezng regular tune-‐ups, changing oil on schedule, and

infla<ng <res to the proper level can improve gas mileage and reduce emissions.

•  Fuel up during the cooler hours of the day—night or early morning. This prevents gas fumes from hea<ng up and producing ozone.

•  Avoid products that release high levels of VOCs. For example, use low-‐VOC paints.

•  Avoid gas-‐powered yard equipment, like lawn mowers. Use electric appliances. Or use people powered tools instead.

Urban Heat Islands

Reading about urban heat islands - https://www.nationalgeographic.org/encyclopedia/urban-heat-island/ 1) What is an urban heat island? 2) What causes an urban heat island to develop? 3) How do urban heat islands affect air quality? 4) How do urban heat islands affect water quality? 5) How do urban heat islands contribute to global warming? 6) What can be done to reduce the effects of urban heat islands? 4

Urban Heat Islands

Urban Forest Strategy •  Vancouver on track to plant 150,000 trees by the year 2020: 126,000 so far.

•  Also working on plan<ng in areas with rela<vely liile tree cover

Recap – what we learned •  Weather and climate

–  How they are related but different concepts –  Local example – wet west coast vs. dry interior –  5 World Climate Zones –  The atmosphere – its importance and layers –  Atmosphere pollu<on – Global, Regional Local examples

Documents

Unit 4 Weather and Climate