Stratospheric Ozone Depletion

9.1 Stratospheric Ozone Depletion Stratospheric ozone location, purpose, reasons for its depletion and consequences when it's not there. - The ozone layer is important to the evolution of life on Earth and the continued health and survival of life on Earth. The ozone depletion is caused by anthropogenic factors, like chlorofluorocarbons, and natural factors, such as the melting of ice crystals in the atmosphere. A decrease in stratospheric ozone increases the UV rays that reach the Earth’s surface. Exposure to UV rays can lead to skin cancer. 9.2 Reducing Ozone Depletion HFC’s - a chemical that contains hydrogen, fluorine, and carbons. 9.3 The Greenhouse Effect Five principal greenhouse gases - carbon dioxide, methane, water vapor, nitrous oxide, and chlorofluorocarbons. Greenhouse effect - results in the surface temperature necessary for life on Earth to exist. GWP - used as a reference point for the comparison of different greenhouse gases and their impacts on global climate change. Compare GWP of different greenhouse gases - Chlorofluorocarbons have the highest GWP, followed by nitrous oxide, then methane. What is different when considering the significance of water vapor as a greenhouse gas? It is the most important greenhouse gas but it does not control the earth's temperature. 9.4 Increases in the Greenhouse Gases Identify the threats to human health and the environment posed by an increase in greenhouse gases. - rising sea levels resulting from melting ice sheets and ocean water expansion, and disease vectors spreading from the tropics toward the poles. What is the College Board’s opinion on the cause of global climate change? - we are the ones causing global warming because of all of the greenhouse gases we emit and carbon emissions. 9.5 Global Climate Change Explain how changes in climate, both short- and long-term, impact ecosystems, specifically ● Marine ecosystems - affected by changes in sea level, some positively, like newly created habitats on now-flooded continental shelves, and some negatively, such as deeper communities that may no longer be in the photic zone of seawater. ● Wind patterns - it can change the circulation patterns and as temperature changes may impact Hadley cells and the jet stream. ● Oceanic currents - it can have a big impact on global climate, especially in coastal regions. ● Soil - changes in temperature and rainfall, which can impact soil’s viability and potentially increase erosion. ● Polar regions - shows faster response times to global climate change because ice and snow in these regions reflect the most energy back out to space, leading to a positive feedback loop. ● Ice and snow - It melts, meaning less solar energy is radiated back into space and instead is absorbed by the Earth’s surface. This in turn causes more warming of the polar regions. ● Positive feedback loops in the arctic - involves melting sea ice and thawing tundra, and the subsequent release of greenhouse gases like methane. ● Coastal populations - the sea levels rise in the coastal areas and it can affect wildlife and human populations. 9.6 Ocean Warming Explain the causes and effects of ocean warming. - affect marine species in a variety of ways, including loss of habitat, and metabolic and reproductive changes. Coral bleaching - occurs when the loss of algae within corals cause the corals to bleach white. Some corals recover and some die. 9.7 Ocean Acidification Explain the causes and effects of ocean acidification. - increased CO2 concentrations in the atmosphere: burning of fossil fuels, vehicle emissions, and deforestation. Ocean acidification damages coral because acidification makes it difficult for them to form shells, due to the loss of calcium carbonate. 9.8 Invasive Species Invasive species - species that can live, and sometimes thrive, outside of their normal habitat. 9.9 Endangered Species How do species become endangered? - being extensively hunted, having limited diet, being outcompeted by invasive species, or having specific and limited habitat requirements. Selective pressures - any factors that change the behaviors and fitness of organisms within an environment. Strategies to protect animal populations from extinction - criminalizing poaching, protecting animal habitats, and legislation. 9.10 Human Impacts on Biodiversity HIPPCO - This stands for habitat destruction, invasive species, population growth, pollution, climate change, and over exploitation describes the main factors leading to a decrease in biodiversity. Habitat fragmentation - occurs when large habitats are broken into smaller, isolated areas. How does domestication affect biodiversity? - can have a negative impact on the biodiversity of that organism, they are used for economic purposes. Strategies to mitigate the impact of biodiversity loss. - creating protected areas, use of habitat corridors, promoting sustainable land use practices, and restoring lost habitats.