Climate and Oceans PDF

12/23/2024 Overview Ocean, Climate and how human Effect it + Lab 1. Earth’s Tilt and 6 Factors Contribute to Orbit Around the Climate & Weather Sun 1 12/23/2024 2 ...

12/23/2024 Overview Ocean, Climate and how human Effect it + Lab 1. Earth’s Tilt and 6 Factors Contribute to Orbit Around the Climate & Weather Sun 1 12/23/2024 2  12/23/2024 6 Factors Contribute to Climate & Weather 5. Oceans: driven by wind! A. Winds near bodies of water Small-scale winds/breezes caused by the difference in the rates of heating 5. Oceans between the land and the water Sea-Breeze: In the morning, the land heats up faster than the ocean, leaving colder air over the ocean. Cold air is denser, therefore, higher pressure The breeze will blow from the sea (high pressure) to the land (low pressure) Land warmer than sea; breeze flows Cool air onshore Warm air ascends descends 3  12/23/2024 Cool air sea_breeze.swf descends Warm air ascends Land cooler than sea; breeze flows offshore Land Breeze – water temperature warm & land cold Evenings During Fall & Winter B. Ocean gyres 5 massive circular current systems caused by the rotation of 5. Oceans Earth and global wind patterns (Coriolis effect) Impact temp, salinity, nutrient distribution globally 4  12/23/2024 C. Upwellings: upward movement of ocean water, driven by winds 5. Oceans Winds push water away from coast and displaced surface water is replaced with deep ocean water Deep water is cold and nutrient-rich due to decomposition that occurs in the benthic zone Plankton can use these nutrients to to produce new food energy, which supports food webs in the ocean 5. Oceans C. Upwellings Take place along Western coasts of some continents Changes in upwelling can greatly affect the local climates and weather patterns El Nino’s and La Nina’s are due to changes in the winds/upwelling off the coast of South America 5  12/23/2024 Every year is either an El Nino or a La Nina, although their strength can change Some years, tropical trade winds slow down or even reverse direction Instead of warm waters moving AWAY from the coast and upwelling occurring to displace the lost water…warm water is pushed TOWARD the coast and no upwelling occurs What are the consequences of this? 6  12/23/2024 Effects of El Nino Upwelling will not occur Nutrients from deep ocean do not reach surface, leading to collapsed food webs Economic loss from fishing Weather Very rainy in South America that can cause destructive flooding Hot, dry weather in Australia can cause droughts and wildfires 7  12/23/2024 Think of La Nina as either an enhancement of the natural La Nina tropical trade winds (E W) or the opposite of an El Nino. So extra-strong tropical trade winds blowing from east to west More upwelling will occur than usual, leading to a biodiverse food web and plentiful fishing revenue Weather Cold and dry in South America Wet in Australia 8  12/23/2024 Freshwater Streams & Rivers Ponds & Lakes Wetland: marsh Wetland: swamps Wetland: bogs Submerged in water for part of or all of the year, but they are shallow enough to support emergent vegetation Estuaries Estuaries are the transition zone between rivers and the ocean Often characterized by brackish waters and sheltered habitats like marshes and mangroves 9  12/23/2024 Marine Wetland: estuary Wetland: seagrass marshes Wetland: mangroves Intertidal Coral Reefs Open Ocean The Hydrosphere One important concept to understand about aquatic ecosystems is that they are all connected Watersheds: a land area that channels all snowmelt and rainfall to a singular point. Groundwater connects marine and freshwater systems 10  12/23/2024 Layers of Lakes Limnetic Zone: photic zone where light penetrates, and algae/ phytoplankton can be found. Profundal Zone: aphotic zone where light does not penetrate. Oxygen-poor (no photosynthesis), sediment-rich and cold. May be missing in smaller lakes. Benthic Zone: the bottom (nutrient-rich due to sedimentation of organic material) 11  12/23/2024 Layers of Oceans In which zone would you find Intertidal Zone: high and low tide creates unique communities the that are adapted to changes in moisture, temperature, light- availability, and salinity. Nutrient-rich. phytoplankton? Why? Pelagic Zone: Open ocean. Nutrient- poor (due to sedimentation of Where are organic material) there the most Hydrothermal Vent: inorganic molecules may be utilized by nutrients? chemoautotrophs (as opposed to photoautotrophs) Why? Abyssal Zone: no light, very cold, very low oxygen, high pressure, nutrient-rich, salty Layers of Oceans In which zone would you find the phytoplankton? Why? Intertidal Zone: high and low tide creates unique communities that are adapted to changes in moisture, temperature, light-availability, and salinity. ____________ Zone: Open Where are there the ocean. Nutrient-________ most nutrients? Why? Abyssal Zone: no ______, very ______, very low __________, high ____________, ______________-rich, ______ 12  12/23/2024 Aquatic Abiotic Factors Light Availability Low High Salinity Freshwater Saltwater pH Acidic (7 Temperature Cold Hot Nutrients/Gases Low High Light Availability Light is needed by photoautotrophs (the most common producer) for photosynthesis Phytoplankton are the primary producers of the pelagic zone Start off most oceanic food webs Other producers include coral and kelp in shallow waters and emergent plants in wetlands The productivity of producers is directly correlated with dissolved oxygen concentration Phytoplankton from space! Zooplankton eat phytoplankton 13  12/23/2024 The human impact you will be learning about is sediment pollution Salinity Salinity is the measure of all the salts dissolved in water. Rain (freshwater)  river (freshwater) estuary (brackish)  Ocean (salty) Salinity increases with depth Like any other abiotic factor, there is a range of tolerance for all species 14  12/23/2024 The human impact you will be learning about is saltwater intrusion into aquifers pH is a measure of acidity The more H+ ions in a concentration, the more acidic the solution pH Rainwater is slightly acidic (6.2), pure water is neutral (7) and seawater is slightly basic (8.6) 15  12/23/2024 The human impact you will be learning about is ocean acidification I’m weak! Temperature Temperature decreases as you move away from the equator Temperature decreases as you increase depth Seasonal turnover: during the fall, the warm surface water of a lake begins to cool, becomes more dense, and sinks. This dense water forces the water at the bottom to rise, "turning over" the layers and recycling nutrients 16  12/23/2024 The human impact you will be learning about is coral bleaching Nutrients The most productive aquatic ecosystems have two qualities: 1. Exposure to light 2. Supply of nutrients Nutrients are supplied by sediments being washed into estuaries from the land OR from upwellings of deep sea ocean currents When phytoplankton have the light and nutrients they need, they reproduce, starting of many aquatic food chains and making marine life possible! 17  12/23/2024 The human impact you will be learning about is dams and… 18  12/23/2024 …algae blooms from fertilizer It’s a big deal… 19  12/23/2024 Human Impact on Aquatic Ecosystems 20  12/23/2024 1. Which site Bell Ringer Question (1, 2 or 3) is most likely experiencing fertilizer run- off? 2. Many environmentalists consider Egypt's Aswan High Dam on the Nile River to be an ecological disaster. Which of the following is the best evidence to support this viewpoint? A. Creation of the dam flooded important archaeological sites. B. Sardine populations near the Nile delta increased exponentially as a result of decreased annual rates of water flow. C. The Aswan High Dam supplies one-third of the electrical power used in Egypt. D. Most of the nutrient-rich silt that the Nile annually deposited downstream is now deposited behind the dam. For Teachers… I do not formally lecture the rest of this PowerPoint on Human Impact on Aquatic Ecosystems. Students explore the human impacts through a self-guided project. This is such a fun and unique activity! The students really love it! PLEASE CHECK IT OUT HERE IF YOU DON’T HAVE IT INCLUDED WITH YOUR RESOURCES! 21  12/23/2024 Human Impact on Aquatic Ecosystems 22  12/23/2024 Construction, mining, & logging can increase sediment run-off 1. Run-off of Turbidity: a measure of dissolved/suspended solutes Happens because roots from vegetation stabilizing soil in place are removed Sediments Light cannot penetrate, decreasing photosynthesis and overall productivity of the aquatic ecosystem Sediment can enter fish gills, causing suffocation and death Roots = Less Soil Erosion and Run-Off! 23  12/23/2024 Deforestation and sediment run-off 2. Saltwater Intrusion Aquifers are being drained faster than they can be recharged by natural rain infiltration Mostly due to irrigation Natural infiltration into aquifer Saltwater Intrusion: the Pumping Well Water movement of saline water into freshwater aquifers Plants watered with saltwater will die! Salt doesn’t evaporate, so it just accumulates on the surface Creates positive feedback loop (salt is dehydrating so the farmer pumps even more water) 24  12/23/2024 3. Ocean Acidification Diffusion of CO2 into ocean is causing water to acidify CO2 reacts with water to produce carbonic acid Carbonic acid dissociates to form free hydrogen ions that readily bind carbonate Marine life needs carbonate to build shells, so it is “stolen” from them. Their shells become weaker, leading to stress and more vulnerable 4. Climate Change – Warming of the Ocean Also (mostly) due to combustion of fossil fuels CO2 is a greenhouse gas, meaning it traps heat in the atmosphere  climate change The ocean has absorbed much of this increased heat Coral reefs very sensitive to warmer water  becoming stressed and causing “bleaching” Loss of biodiversity 25  12/23/2024 A coral ejecting zooxanthellae caught on camera for the first time 5. Run-off of Fertilizers Causing Eutrophication Fertilizer (mostly nitrogen and phosphorous) that we use to help crops grow can run-off into local waters Algae “feeds” on the fertilizer and blooms Algae can be so thick, it blocks sunlight Algae dies as quickly as it blooms and must be decomposed by bacteria Bacteria sucks up the oxygen for decompositions, leading to death of marine life 26  12/23/2024 Other Common Fertilizer Applications 5. Eutrophication 27  12/23/2024 Florida Red Tide (algae blooms don’t have to be green) Dams act as a sediment trap, decreasing downstream supply Can result in eroding coastlines 6. Dams Sediments contain nutrients vital to plankton (the start of most aquatic food chains!) Migration/Reproduction of some fish (like salmon) impacted 28  12/23/2024 Mangroves are one of the most biodiverse ecosystems, home to many bird and fish populations. Fish nurseries: many marine fish lay eggs here so baby fish can grow up sheltered by the root systems to grow big before swimming out to sea! Mangroves prevent coastal erosion with their enormous root systems Mangroves have thick organic sediment layers that suck up water like a sponge to reduce flooding All of these ecological services disappear when they are destroyed for urban or agriculture land 29  12/23/2024 The Florida Everglades are the largest mangrove habitat in the world In Florida, the total acreage of wetlands has decreased by about 44 percent over the past 150 years due to urbanization & agriculture 30  12/23/2024 No mangroves No baby fish No adult fish Ocean food web Fisheries collapse falls apart 31  12/23/2024 7. Overfishing Loss of fish stocks caused by new fishing technologies that are too efficient and largely unregulated Tragedy of the Commons No country has an incentive to protect fish stocks or replenish them because they do not belong to one nation Result: Decline of a fish population by 90% or more since 1950 Bycatch: unwanted catch that is often killed (ex. turtles, sharks, dolphins) Bycatch in New Zealand 32  12/23/2024 8. Loss of Keystone Species Species are being lost worldwide at alarming rates due to many things, such as habitat loss or hunting. Keystone Species have a disproportionately larger impact on the ecosystem then other species Loss of a keystone species will result in a trophic cascade of biodiversity loss Ex. Otters were hunted in California for their fur, leading to a trophic cascade of the kelp forests 9. Invasive Species Non-native species that have been introduced by HUMANS Tend to be generalists that can outcompete native specialists Disrupt food webs and decrease biodiversity This will make the ecosystem more vulnerable to further disturbances Ex. The lionfish in the Florida Keys (from the Indo-pacific) have few predators, each many different animals, and fast reproduction rates 33