APENV Unit Nine main concepts

Importance of stratospheric ozone to life on earth

• important to the evolution of life on Earth and the continued health and survival

Causes of stratospheric ozone depletion

• Anthropogenic factors, like chlorofluorocarbons (CFCs)

• Natural factors, like melting of ice crystals in the atmosphere at the start of the Antarctic spring

What happens when there is a decrease in the stratospheric ozone

UV rays that reach the earth’s surface increases

Exposure to UV rays

leads to skin cancer and cataracts in humans

How can ozone depletion be mitigated? Include an example

By replacing ozone-depleting chemicals with substitutes that do not deplete the ozone layer. One example is hydrofluorocarbons (HFC) as a replacement

Principal greenhouse gases

• carbon dioxide

• methane

• water vapor

• nitrous oxide

• chlorofluorocarbons (CFCs)

Why does water vapor not contribute to climate change

it has a short residence of time in the atmosphere

the greenhouse effect

results in the surface temperature necessary for life on Earth to exist to increase by trapping it

Greenhouse gas potency

• Carbon dioxide is used as the reference point; has a global warming potential as 1.

• Chlorofluorocarbons (CFCs) have the highest GWP, then nitrous oxide, then methane

Sources of carbon dioxide

• Combustion of fossil fuels

• Deforestation

• Industrial processes

• Agriculture

• Respiration by living organisms

Sources of chlorofluorocarbons (CFCs)

• Aerosol propellants

• Refrigerants

• Solvents

• Foam-blowing agents

Sources of nitrous oxide

• Agricultural activities

• Fossil fuel combustion

• Industrial processes

• Waste management and treatment systems

sources of methane

• Natural sources: Wetlands, termites, oceans

• Human activities: Livestock farming, rice paddies, landfills, fossil fuel production

Excess greenhouse gases in the atmosphere causes

global climate change

global climate change results

• rising temperatures

• rising sea levels due to melting ice sheets and ocean water expansion

• displacement of coastal population

• disease vectors spreading from the tropics towards the poles

• changes in population dynamics and population movements

How has the shifts in global temperatures through time been measured?

CO2 data and ice cores

Positive and negative effects of marine ecosystems by changes in sea level

• Positive: newly created habitats on now-flooded continental shelves

• Negatively: deeper communities may no longer be in the photic zone of seawater

What helps transport heat throughout the Earth

winds generated by atmospheric circulation

How can climate change effect wind

• may change circulation patterns

• temperature changed may impact hadley cells and the jet stream

Climate change impact on oceanic currents

• oceanic currents/oceanic conveyor belt carry heat throughout the world

• currents can change as a result of climate change and impact costal regions

climate change impact on soil

• through changed in temperature and rainfall

• impact soil’s viability and potentially increase erosion

Climate change impact on polar regions

• showing faster response time to climate change

• ice and snow is reflecting most of the energy back to space, creating a positive feedback loop

• climate change causes ice and snow to melt, so less solar energy is radiated back into space, meaning the earth is absorbing more energy, causing warming

• melting sea ice and thawing tundra can lead to a subsequent release of greenhouse gases like methane and hurt species dependent on the ice

Cause of ocean warming

increase in greenhouse gases in the atmosphere

ocean warming effects

• loss of habitat for marine ecosystems

• metabolic and reproductive changes

• coral bleaching

Ocean acidification

decrease in pH of the ocean, primarily due to increased CO2 concentration in the atmosphere

Process of ocean acidification

• as CO2 is released into the atmosphere, the ocean absorbs a large part of that, causing it to become more acidic

Causes of ocean acidification are

anything leading to an increase in CO2 in the atmosphere

• burning fossil fuels

• vehicle emissions

• deforestation

how does ocean acidification affect the corals

makes it difficult for corals to form shells due to the loss of calcium carbonate

Invasive species

species that can live and sometimes thrive outside of their normal habitat. Considered invasive when they threaten native species

what type of species are invasive species and what does that mean?

often generalist, r-selected specise, meaning they can outcompete native species for resources

Causes of species becoming endangered

• extensive hunting

• limited diet

• outcompeted by invasive species

• having specific and limited habitat requirements

What type of species are less likely to face extinction?

Species that can adapt to changed in their environment

Selective pressures

factors that change the behaviors and fitness of organisms within an environment

What do species compete for

resources such as

• territory

• food

• mates

• habitat

strategies to protect animal populations

• criminalizing poaching, protecting animal habitats, legislation

Main factors leading to a decrease in biodiversity

• HIPPCO: habitat destruction, invasive species, population growth, pollution, climate change, and over exploitation

Habitat fragmentation

when large habitats are broken into smaller, isolated area. Causes include construction of roads and pipelines, clearing for agriculture and development, and logging.

How does global climate change cause habitat loss

• changes in temperature

• changes in precipitation

• sea level rise

Domestication on organism

has a negative impact on biodiversity

ways the impact of loss of biodiversity can be mitigated

• creating protected areas

• habitat corridors

• promoting sustainable land use practices

• restoring lost of habitats