Unit 6

Question 1

The atmosphere is

Answer 1

A dynamic system essential to life on earth that have undergone changes throughout geological time

Question 2

The atmosphere is composed of

Answer 2

nitrogen and oxygen with smaller amounts of carbon dioxide, argon water vapor and other gases

Question 3

Troposphere

Answer 3

Closest layer to the earth’s surface and includes where we live. 10 km above sea level

Question 4

Greenhouse effect

Answer 4

​The ‘greenhouse effect’ is an atmospheric heating phenomenon in which the Earth experiences rise in temperature because certain gases (water vapor, carbon dioxide, nitrous oxide, and methane) in the atmosphere allow incoming sunlight to pass through but trap heat radiated from the earth’s surface.

Question 5

Stratosphere

Answer 5

10 to 50km. Absorbs ultra violet radiation from the run.

Question 6

Mesosphere

Answer 6

50 to 80km. Without the presence of ozone or other particulates to absorb UV radiation, the temperature declines with height. Coldesr part

Question 7

Thermosphere

Answer 7

80km to between 500km and 1000km.

Question 8

What is the albedo effect and its role managing the earths temperature

Answer 8

Albedo is a measure of the reflectivity of a surface. The albedo effect when applied to the Earth is a measure of how much of the Sun’s energy is reflected back into space. More water vapour in the atmosphere means more cloud formation. More clouds lead to increased albedo of the earth.

it changes how much solar energy is reflected by the Earth as opposed to how much is absorbed. This changes how Earth’s energy budget balances and thus changes Earth’s heat balance.

Question 9

What is stratospheric ozone

Answer 9

a key component of the atmospheric system because it protects living systems from the negative effects of ultraviolet radiation from the sun

Question 10

Dynamic equilibirum in stratospheric ozone

Answer 10

some ultraviolet radiation from the sun is abrobed by the stratospeheric ozone causing ozone molecule to break apart. Under normal conditions the ozone molecule with reform. This ozone destruction and reformation showcases dynamic equilibrium.

Question 11

Consequences of UV radiation on plants/on animals

Answer 11

Damages human living tissues, increase cataracts, mutation during cell division, skin cancer etc

on plants
damages biological productivity especially plankton that fors at basis of aquatic food wevs

Question 12

Threats to stratospheric ozone

Answer 12

Collectivley called (Ozone depleting substances) (ODS). Often contain clorine or bromine.

Chloroflurocarbons (CFS) are the main grouos of ODS. These are mainly used in coolants in refrigeratiors and air conditioning systems, propellants in aerosol cans, cleaning agents for electrical parts, blowing agents in plastic foam.

Question 13

Changes in stratospheric ozone levels

Answer 13

Over time variation. Long term and seasonal changes have been recorded.

Since 1970s there has been a reduction in oone levels around the world.

Ozone levels are their lowest at summer in the Antartic regions. Sunlight releases chlorine and other chemicals that cause ozone destruction.

Question 14

Management of stratospheric ozone

Answer 14

International agreement: Montreal Protocol signed by 197 nations.

Reduction of ozone depleting substances. Make laws and regulations to decrease the consumption and production of halogened organic gases like CFS.

Question 15

Challenges for dealing with Ozone depleting substances

Answer 15

1. Long span of ODS. They have an effect for a long time after production and use have stopped.
2. ODS present in discarded equipment and these may leak into the environment
3. lack of alternatives. cheaper alternatievs to ODS may not be available
4. Ilegal trade. Might be driven by higher cost of alternatves. Less effective replacements
5. Lack of policing and enforcemnent

Question 16

Pollution management approaches to manage ODS

Answer 16

Altering human activity
- campaigns to educate the public to stop buying ODS. Pressure on industry to use suitable replacements of ODS. ex. hydrocarbons can replace CFS in refrigerators

Controlling the release of the pollutant
- Ban on the production. Like international protocol (montreal)

Clean up and restoration
- removal and destruction of existing ODS.

Question 17

Primary pollutants

Answer 17

Primary pollutants from the combustion of fossil fuels include carbon monoxide, carbon dioxide, black carbon or soot, unburned hydrocarbons, oxides of nitrogen, and oxides of sulfur.

Question 18

Secondary pollutants

Answer 18

In the presence of sunlight, secondary pollutants are formed when primary pollutants undergo a variety of reactions with other chemicals already present in the atmosphere.

Question 19

When does Photochemical smoke occur ?

Answer 19

Photochemical smog occurs when sunlight activates reactions between nitrogen oxides (NOx) and volatile organic compounds (VOCs) resulting in the formation of ozone and peroxyacyl nitrates (PAN).

Question 20

Photochemical smog most likeley to be formed under these conditons

Answer 20

Ensure you understand that formation of smog is affected by climate, topography, population density and amount of industry and vehicles.

High fossil fuels emissions
High levels of sunlight (highest levels of ozone)
Dry weather conditions as it does not wash the pollutants out
When a thermal inversion occurs (Thermal inversions occur due to a lack of air movement when a layer of dense, cool air is trapped beneath a layer of less dense, warm air. This causes concentrations of air pollutants to build up near the ground instead of being dissipated by “normal” air movements.)

Question 21

Impact of tropospheric ozone

Answer 21

Highly reavtive gas
Causes inflammation of the lungs causing coughing, wheezing and contributing to asthma
Reduces lung function
Dmages cells in the leavs
Damages fabrics like rubber and plastic

Question 22

Urban pollution manageement for smog

Answer 22

• use of legislating to control relase of pollutants
• clean up and restoration
• industrial smog

Pollution management strategies include:
– altering human activity to consume less fossil fuels—example activities
include the purchase of energy-efficient technologies, the use of public
or shared transit, and walking or cycling
– regulating and reducing pollutants at the point of emission through
government regulation or taxation
– using catalytic converters to clean the exhaust of primary pollutants
from car exhaust
– regulating fuel quality by governments
– adopting clean-up measures such as reforestation, regreening, and
conservation of areas to sequester carbon dioxide.

Question 23

Legislation of photochemical smog

Answer 23

International agreements (e.g. 1999 Gothenburg Protocol)

Legislating setting emission standards (lower sulfur fuel, adoption or solar or wind energy)

Building regulations (standards that require improvements in energy efficiency of buildings)

Planning regulations
- cycle paths
- road lanes restricted to public transport

Question 24

Clean up measures and restoration of photochemical smog

Answer 24

Devices called “scrubbers” can be used by industry and power stations to filter emissions prior to discharge to remove primary pollutants such as particulate matter and sulphur dioxide.

However, once the photochemical smog is formed, ozone and PAN are highly reactive and are removed by reactions with other chemicals, hence are not long lasting.

Question 25

What is Acid deposition

Answer 25

This acid deposition occurs as a result of primary pollutants of sulphur dioxide and nitrogen oxides reacting in the atmosphere to form secondary pollutants of sulphuric acid and nitric acid respectively. This results in the pH declining to below five.

Acid rain, or acid deposition, is a broad term that includes any form of precipitation with acidic components, such as sulfuric or nitric acid that fall to the ground from the atmosphere in wet or dry forms.

Question 26

Acid deposition in aquatic systems

Answer 26

Can enter as precipitation or rain or runoff. Lower PH of aquatic ecosystem beyond the ability of some organisms to survive. Loss of speciesimpact food chain and reproductive fitness.

Question 27

Acid decompositin in terrestial ecosystems

Answer 27

Leaching of plant nutrients. Reduces the nurtrients for plant uptake.
Can damage root systems
can contaminate drinking water supplies

Question 28

The possible effects of acid deposition on soil, water and living
organisms include:

Answer 28

– direct effect—for example, acid on aquatic organisms and
coniferous forests
– indirect toxic effect—for example, increased solubility of metal (such as
aluminium ions) on fish
– indirect nutrient effect—for example, leaching of plant nutrients.

Question 29

Main sources of acid deposition

Answer 29

The main sources of sulphur dioxide and nitrogen oxides, the primary pollutants that result in formation of acid rain include:

Stationary sources (i.e. fixed point sources) such as power station, industry and domestic boilers.
Mobile sources which are predominately vehicles.

Question 30

management of acid deposition (guide)

Answer 30

– altering human activity—for example, through reducing use, or
using alternatives to, fossil fuels; international agreements and
national governments may work to reduce pollutant production
through lobbying
– regulating and monitoring the release of pollutants—for example,
through the use of scrubbers or catalytic converters that may remove
sulfur dioxide and oxides of nitrogen from coal-burning powerplants
and cars.

Question 31

More methods

Answer 31

Changing human behavior
- conservation and reduce energy demand
- alternative energy sources
-reduce individual car use

Electronic instruments
- pollution tax
- change road toll and car parking fees
- subsidies for technologies that reduce emissions

Technology
- catalytic convertes in motor vehicles to reudce emissions of nitrogen oxides
- switch to cleaner fueles
- improve energy source effeicny

legislation
- emission standards

Question 32

clean up restoration of acid deposition

Answer 32

Clean-up and restoration measures may include spreading ground limestone
in acidified lakes or recolonization of damaged systems—but the scope of
these measures is limited.