Population And Environment 3 Flashcards
Ozone depletion
- Ozone is a gas found in the upper atmosphere which forms a thin layer which absorbs harmful Ultraviolet radiation from the sun.
- Lower concentrations of ozone - more UV radiation reaches the earth’s surface which can have serious impacts on humans, flora and fauna.
- This has been depleted by chemicals such as chlorofluorocarbons (CFCs) which was used in aerosols, fridges and insulation until the late 20th century
- Banned in 1987 by the Montreal Protocol (UN environmental programme - UNEP)
What health problems can ozone depletion cause?
SKIN CANCER - long term exposure to the sun - harmful UV rays which cause genetic mutations in the skin that has been exposed to the sun. Or short periods of intense sun exposure and burning.
Most vulnerable include: elderly, fair skinned, people living at low latitudes and males (due to more outdoor work)
How to protect against sun cancer
Sunscreen, factor 50+, wear long-sleeve troops, hats and glasses, stay inside during hot periods of the day (10am-3pm, mid day sun)
MCATARACTS - When the lens of the eye becomes damaged - causing cloudiness/ blurred vision and eventually blindness. It can caused by old age, burning fuelwood, smoking, diabetes, poor nutrition but also over-exposure to UV radiation
Cataracts are the leading cause of blindness in the world, especially in LDEs where there is a lack of access to surgery to remove cataracts.
Prevention - Need to wear good quality sunglasses ‘wrap around style’ blocks harmful UV radiation. The only effective treatment is surgery to remove the cloudy lens and replace with a lens implant.
Climate change
global warming and rising temperatures can bring fewer winter death and increase food production in some areas
Thermal stress and heatwaves
Heatwaves may become more common and intense and many areas will experience warmer summers (UK Summer 2022). This will cause thermal stress leading to deaths amoungst the elderly and amoungst people with cardiovascular and respiratory diseases.
Heatwaves can cause dehydration, overheating, heatstroke, and heat exhaustion. High risk to young, elderly and ill people.
Heatwaves also cause other health risks such as:
- More photochemical smog - UV rays mixing with nitrogen oxide in the atmosphere - can causes eye and respiratory diseases
- Growth of blue-green algae in water courses which can harm/ kill aquatic life including fish as well as toxic algal blooms, causing problems for public recreational water activities
- Wildfires
- Water shortages
- Cold spells
Emergence and changing distribution of vector borne diseases
Disease vectors can survive and reproduce with a range of optimum climatic conditions. Changes to temperature and rainfall regimes resulting from climate change will alter the geographical distribution of optimum conditions for most vectors.
Malaria and dengue
Increase in mosquitoes carrying Malaria which are normally confined to tropical areas - rising temperatures will increase their range.
Low Income Countries (LICs) are more vulnerable
Lyme disease
Most common vector borne disease in temperate climates in the northern hemisphere including Europe and USA.
Transmitted to humans from the bite of an infected deer tick. Warmer conditions will increase their distribution and numbers.
It is an emerging vector-borne disease thought to be associated with warmer and more humid conditions
Over the course of the 21st century, how much is population predicted to rise by?
75% reaching 10.9 billion by 2100
What is global life expectancy predicted to be by 2050?
77.1 years
Constant variant, medium variant and high/low variant
Constant variant - fertility based on current levels remaining constant = this is unrealistic
Medium variant - the most likely scenario and the one UN use for projection
High and low variant - this assumes that fertility rates are o.5 higher or lower than the medium variant
Challenges and opportunities of future-population environment relationships
CHALLENGES:
- Depletion of fossil fuels
- Increased climate change
- Strain on water resources locally
- Increased water pollution
- Increased consumption
OPPORTUNITIES:
- Energy transition shift to renewable energy
- Integrated water resource management to increase supply and storage
- Shift to healthier, more sustainable diets
