Unit 9 Global Change APES

Ozone’s purpose in the stratosphere

absorb UV-C and much of UV-B radiation

Human health Benefits of stratospheric ozone

prevent skin cancer & caracts, UV-B & C mutate DNA (skin cancer) & cause oxidative stress in eyes

Tropospheric ozone effects

resp. irritant , damage plant tissues, and precursor to photochemical smog

How does straospheric ozone form

UV-C breaks O2 into free oxygen atoms which from O3 (ozone) (also turns ozone back to o2 as well)

Primary anthropogenic cause of O3 breakdown

CFCs (chloroflurocarbons)

Where do CFCs come from

refrigerant chemicals and propellants in aerosol containers

How are CFCs destructive to stratospheric ozone?

UV radiation causes free chlorine atoms to seperate from CFCs and since chlorine is rlly electronegative it bonds to free O2 from O3 lessenign the amount of ozone -> this process continues (free Cl keep breaking down O3)

NATURAL OZONE DEPLETION

Montreal Protocol (87’)

a global agreement to phase CFCs out of production in refrigeratios, aerosols, and other uses

Replacement for CFCs

HCFCs (CFCs with hydrogen)

HCFS shortcomings

still deplete O3 and is a GHG but to a lesser extent than CFCs

Replacement for HCFs

HFCs bc don’t have chlorine so no more ozone depleting

Solar Radiation reaching Earth

not all solar radiation reaches earth surface, 25% reflected back into space by cloud & atm, 19% absorbed by atm, and rest stays on earth surface by being absorbed or reflected based on albedo

Greenhouse Effect

gases in earth’s atmosphere trap heat from sun & radiate it back down to earth (part of infrared radiation that comes back to earth)

Infrared Radiation

the sunlight released from Earth’s surface back into the atm and absorb by greenhouse gases then radiates into space and earth

Most important GHGs

CO2 (carbon dioxide), CH4 (methane), Nitrous Oxide (N2O), and CFCs/HCFs/HFCs

CO2

FF combustion, decomposition, and deforestation

Methane

Natural gas extraction & combustion, animal agriculture, anaerobic decop (esp permafrost thaw)

Nitrous Oxide (N2O)

comes from agricultural soils (bc synthetic fertilizers) -denitrification of nitrate

Technically a greenhouse gas but very weak

water vapor

Water vapor

comes from evaporation & transpiration from plants

Global Warming Potential (GWP)

Measure of how much a given molecule of gas can contribute to the warming of the atmosphere over a 100 year period, relative to CO2

What 2 factors is GWP based on?

residence time (how long last in atm) + infrared absorption (how well gas absorb & radiate infrared radiation)

Best to Worst GWP

CO2 -> methane -> N2O -> CFCs

What causes sea level to rise?

Thermal expansion (water molecules move slightly further apart when they’re heated -> all ocean water molecules move slightly apart) & increased GHG ->melts ice sheets -> water goes to ocean

Env impacts of Sea Level Rising

flooding of coastal habitats, saltwater intrusion into freshwater systems, and loss of biodiversity in coastal ecosystems

Human Impacts of Seal Level Rising

displacement of coastal populations, damage to infrastructure, and economic losses from tourism/agriculture

How does climate change affect disease vectors

expands range and season for vectors like mosquitoes and ticks; increases disease transmission (malaria, dengue, Lyme)

Earth’s historic climate change

natural fluctuations like glacial and interglacial periods over millions of years

Evidence for Earth’s historical Climate Change

ice cores, tree rings, ocean sediment, and fossil records

Effects of Climate Change

extreme weather, biodiversity loss, ocean acidification/warming, sea level rise

Climate Change Impacts of Coastal Communities

increased flooding, erosion, infrastructure damage, displacement, LOSS of barrier islands tha protect ecosystem from wind & waves

Climate Change Impact on Atmospheric Currents

widening & weakening of hadley cell and alters jet streams *artic warm faster) , causes extreme weather like polar vortexes or heat waves

Climate Change Impact on Marine Ecosystems

altered range of marine ecosystems bc new marine habitats are formed and altered range for organisms bc warm water holds less O2,ex-coral bleaching, migration changes, disrupted food chains

Climate Change Impact of Ocean Circulation

slows thermohaline circulation, disrupts nutrient and heat distribution

Unequal Global Warming

Arctic warms faster than tropics; developing countries face harsher effects (bigger gap in temp overall) esp from permafrost (permantey frozen tundra soils) that begin to thaw and release methane and CO2from anaerobic decomposition

Climate Change impact of Polar Ecosystems

sea ice loss threatens polar species; habitat degradation

Positive Feedback loop with Global Warming

melting ice → less albedo → more warming → more melting

Negative Feedback loop with Global Warming

more clouds → more reflection of sunlight → cooling effect

Why does the ocean get warmer?

Atm get warmer -> go to ocean spec ocean radiated back to earth by GHG, water has high specific heat capacity so it takes a lot of the heat

Ocean Warming Effects of Marine Species

disrupts migration, lowers oxygen, causes metabolic stress

Climate Change Effect on Coral Reefs

warming ocean cause thermal stress -> coral bleaching and infectious disease, seal level rise and cause sedimentation -> smothering of coral, changes in storm patterns -> stronger more frequent storms -> destruction of reef structure, change in prec -> increased runoff of freshwater sediment & land based pollution -> algae bloom & they reduce light

Coral Bleaching

algae have narrow temp tolerance so once temp rise they leave, coral lose color (bc algae form the color), coral and algae earlier had a mutalstic relationship where coral provided habitat for photosynthetic algae (zooxanthellae) supplying coral with sugar and, Co2& detritus (nutrient rich org matter), no more algae so coal become stressed and more vulnerable to disease without algae (main food source)

What causes Ocean Acidification

higher CO2in atm -> increased ocean CO2 (by diffuse), CO2 forms carbonic acid H2CO3 & dissocates HCO3- & H+ ion so make ocean more acidic/lower pH prevents the formation of calcium carbonation shells Ca + CO32

Purpose of Calcium Carbonate for Marine Ecosystems

carbonate ions became less available as they form carbonic acid (H2CO3) and bicarbonate acid (HCO3- & H+), marine animals use calcoum carbonate for there shells so they cannot form them as much and their shells start to break down bc of the pH decrease

Anthropogenic causes of ocean acidficaton

anything that causes for CO2 so fossil fuel combutison, deforestation (prevent co2 sequestration, and coal/gas combustion

Characterstics of Invasive species

no nat predators, highly competitive, thrive in non-native habitat, at biotic potential, highly adaptable, usually r selected (reproduce fast) and generalist (wider range of tolerance)

Zebra Mussel

grow rlly fast and spread vis ship ballast water, eat algae which is bad bc many species rely on them

Kudzu Vine

was planted to reduce soil erosion in U.S, grow rlly fast, in south U.S, outcompete native by taking sunlight

Asian Carp

brought in to control algae growth in aquatic farm, escaped to mississippi river and outcompeted native fish for resources, and decreased fisherign production & value (bc they not tasty enough to sell)

Emerald Ash Borer

spread by wood packing material, larvae lay in bark and eat their way into phloem, disrupt tree nutrients, and have an expanded range due to global warming

Cane Toad

introduced to australia as a way to limit cane beetles but ended up eating everything else so then like everything else decrease so much (amphibians and small reptiles)

Pythons (FL)

brought to florida as pets, they grow rlly big and are scary, then they are put back into the wild and eat like everything thre (mammal population decline significantly), and they are aggressive hunters with no natural predators

Invasive Species’ Control/Removal Methods

physical/chemical/biological control, prevention, and education

Characterstics of Invasive species

no nat predators, highly competitive, thrive in non-native habitat, at biotic potential, highly adaptable, usually r selected (reproduce fast) and generalist (wider range of tolerance)

Zebra Mussel

grow rlly fast and spread vis ship ballast water, eat algae which is bad bc many species rely on them

Kudzu Vine

was planted to reduce soil erosion in U.S, grow rlly fast, in south U.S, outcompete native by taking sunlight

Asian Carp

brought in to control algae growth in aquatic farm, escaped to mississippi river and outcompeted native fish for resources, and decreased fisherign production & value (bc they not tasty enough to sell)

Emerald Ash Borer

spread by wood packing material, larvae lay in bark and eat their way into phloem, disrupt tree nutrients, and have an expanded range due to global warming

Cane Toad

introduced to australia as a way to limit cane beetles but ended up eating everything else so then like everything else decrease so much (amphibians and small reptiles)

Pythons (FL)

brought to florida as pets, they grow rlly big and are scary, then they are put back into the wild and eat like everything thre (mammal population decline significantly), and they are aggressive hunters with no natural predators

Invasive Species’ Control/Removal Methods

physical/chemical/biological control, prevention, and education

Characterstics of Invasive species

no nat predators, highly competitive, thrive in non-native habitat, at biotic potential, highly adaptable, usually r selected (reproduce fast) and generalist (wider range of tolerance)

Zebra Mussel

grow rlly fast and spread vis ship ballast water, eat algae which is bad bc many species rely on them

Kudzu Vine

was planted to reduce soil erosion in U.S, grow rlly fast, in south U.S, outcompete native by taking sunlight

Asian Carp

brought in to control algae growth in aquatic farm, escaped to mississippi river and outcompeted native fish for resources, and decreased fisherign production & value (bc they not tasty enough to sell)

Emerald Ash Borer

spread by wood packing material, larvae lay in bark and eat their way into phloem, disrupt tree nutrients, and have an expanded range due to global warming

Cane Toad

introduced to australia as a way to limit cane beetles but ended up eating everything else so then like everything else decrease so much (amphibians and small reptiles)

Pythons (FL)

brought to florida as pets, they grow rlly big and are scary, then they are put back into the wild and eat like everything thre (mammal population decline significantly), and they are aggressive hunters with no natural predators

Invasive Species’ Control/Removal Methods

physical/chemical/biological control, prevention, and education

HIPPCO

Habitat Fragmntation/Loss, Invasive Species, Population Growth, Pollution, Climate Change, and Over Exploitation

Habitat Fragmentation

Separating one large habitat into 2 by adding roads, pipelines, agri us, or logging

Metapopulations

Populations separated by space but interacting via migration

Habitat Corridors

areas that allow gene flow between disconnected habitats -> improving genetic diversity

Edge Effect

When 2 diff ecosystem like forest-grassland or ocean-river meet and have diff charac in middle of ecosy -> higher range of tolerance in middle which is good for some species but bad bc is good for potentially disruptive species

Mitigating Biodiversity Losses

protecting & connecting habitats (national parks or natural preserves) like with wildlife corridors, sustainable land use (parks, urban garden, or green roofs), or restoring lost habitats by replanting clear-cut forests