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SCI 256 – People, Science and the Environment Environmental Science

SCI 256 – People, Science and the Environment Environmental Science

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SCI 256 – People, Science and the Environment Environmental Science

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  1. SCI 256 – People, Science and the EnvironmentEnvironmental Science Week 1 - Environmental Science, The Scientific Method, and Environmentalism, Human Populations

  2. Tips on the Power Point Presentations… • The Yellow normal text (or yellow, not orange titles) are concepts that are MOST important and are the material that is quizzable/testable. • The presentations (especially those online) are a compilation of previous courses I have taught and are TOO long and detailed for a 5 week lecture run. I will edit (skip by quickly) things that are TOO deep (and will edit those slides out when I next teach. I’m still reducing!)

  3. What a science course is… • Not as much discussion as you are used to. • A lot more PRESENTATION with team • You need input at some point to be able to discuss concepts… • Concepts are encapsulated in terminology. • Learning the terms is very important.

  4. Terminology • Make flash cards • Quiz yourself • Come up with memory tricks (I’ll supply the ones I’ve heard of or the ones in the textbook).

  5. More expectations • We’ll stick very very closely with the textbook • You will be able to go from text to class to (hopefully) the final quiz with everything being reinforced

  6. Repeated Exposure • You will hear the same concepts over and over from different directions. Multiple exposures= hopefully better retention. • The repeated points: • Sources and sinks (pollution) of resources • Energy and the ‘cycling’ resources • What are the major climate issues in the news and why? • Who decides what and how to fix problems? • Cost/Risk Assessment – in all parts of life • Ask questions!

  7. Today • Environmental Science • The Scientific Method (your pre-class paper) • The Development of Environmentalism • Population of the Earth (humans and other things)

  8. Chapter 1 • Our Environment – changes? • Really?

  9. Environmental Science • Don’t be intimidated by the term… we’ll break it down • It is a mixture of many disciplines…which means you only need to get the basics of a wide range of concepts…you can’t (at this stage) dig into the deeper material. • Everything in this section will be repeated and expanded upon in the next 4 weeks.

  10. Breaking it down… • Biology/ecology, geography, chemistry, geology, physics, economics, sociology/demography, cultural anthropology, natural resources management, agriculture, engineering, law, politics, and ethics. • Sounds broad enough? • Sounds fun?

  11. We’ll be concerned with… • Human populations • Natural resources • Pollution – natural and human in origin • air • water • soil

  12. Goals…and the problem… • We need to try to find out how the world really works. • Scientific knowledge is needed, and needs to be reliable, repeatable, complete. • Political decisions often need to be made before science has had time to repeat observations enough for them to become reliable and complete.

  13. Issues. • Which issues are real? • Which issues are the most serious? • Which issues can be addressed? • What will it cost civilization and the global resource pool to address issues? • Is it always ‘gloom and doom’?

  14. The extremes • On a scale of 1 – 10 how do you feel? (Use any # 1 thru 10) • 1: Most if not all the environmental issues brought before the public are extreme, save-the-earth, tree-hugging motivated attacks on our capitalistic economy. • 5: Some environmental issues are wrongly ignored by the population while some environmental issues are over emphasized by the media and policy makers. • 10: Environmental issues are routinely ignored and downplayed by capitalistic interests and attention to corporate profits.

  15. We’ll look at each issue and look for signs of over or under-play in public awareness • Personal observation – some issues are taken beyond the middle ground to overcome societal inertia • There is a need to bend the metal too far the other way to get it to relax to the correct position • We’ll see if this hypothesis holds true.

  16. Environmental Sustainability • A BIG term in environmental science • “It’s the ability to meet humanity’s current needs without compromising the ability of future generations to meet their needs.” • Using resources and earth systems without overusing and/or damaging them.

  17. Environmental Sustainability details • Our actions effect the health and well-being of the natural environment including living things. • Earth’s resources are not in infinite supply – some regenerate (water, wood)- some don’t (coal, oil, metals) • Products we consume always have a cost to the environment associated with them • Everybody needs to play a part for environmental sustainability to be practiced successfully.

  18. Are we operating with sustainability? • Many scientists think we are not: • we use nonrenewable resources for fuel (oil, coal) • we use renewal resources faster than they can be replenished • we put out more toxins (a broad word!) than the environment can absorb/break down in many places. • the number of humans on the planet continues to increase rapidly

  19. So why not reduce the consumption and growth? • Who does it and how much? • How do you enforce it? • Who has the right to dictate the changes and policies? • Society, ecology and economics all matter!

  20. Things need to grow and develop: Sustainable Development • 1992 U.N. Conference on Environment and Development

  21. The components: • Goal: Improve the living conditions of all humans while creating environmental sustainability. • Environmentally Sound Decisions • Economically Viable Decisions • Socially Equitable Decisions QUITE a balancing act! (we’ll see the result of this process as the weeks go by)

  22. Our Impact so far

  23. What just one family can do!

  24. Population is on the rise • 1800 = 1 billion world wide • 1930 = 2 billion • 1960 = 3 billion • 1975 = 4 billion • 1987 = 5 billion • 2000 = 6 billion • 2005 = 6.45 billion • 2007 = 6.7 billion • 2012= 7.035 billion

  25. Poverty • High population numbers and poor management of resources leads to poverty. • Defined by the world bank as incomes less than $1/day (one measure of poverty) • Approx. 1.2 billion live at this level • Approx. 2.8 billion are unable to meet basic needs of shelter, food, clothing, education and health. • Approx. 828 million consume than 80% of the recommended daily caloric intake

  26. Flattening out of populations? • We may see it level off by the end of the 21st century at about 7.9 to 10.9 billion.

  27. Consumption – another measure of population + resources • The US consumes more per person (capita) than people in developing countries do. • (We also produce more that is sold and distributed world wide more per capita than any country in the world). • But this means more concentrated energy, resource use and waste/pollution here than elsewhere.

  28. Your first look at pollution and a theorized result… (how it might come home to us) • Pollution: Any alteration of the physical environment that harms the health or survival of any living organisms. • Endocrine Disrupters • There is growing evidence that the direct impact of many chemicals released to the environment from manufacturing and agriculture change the operation of the human endocrine system. • PCB’s and dioxins (chlorine containing chemicals), heavy metals like lead, mercury and pesticides like DDT, kepone, dieldrine, chordane, and endosulfan + some plastic additives like phthalates can all cause our bodies to change chemically (in a broad sense)

  29. Stuff inside – and critical thinking. • The CDC (center for disease control) in 2001 reported elevated levels of 28 different such chemicals/elements in a sample of the civilian U.S. population. In 2012 112 environmental chemicals now followed. • BUT 24 of the 28 chemicals (now 112) had NOT been tested before… they might be naturally picked up from the environment and stored in the body. • The best you can say is we have a baseline now…we don’t know if those have actually increased. • http://www.cdc.gov/exposurereport/pdf/FourthReport_UpdatedTables_Feb2012.pdf

  30. The concern… • Endocrine Disrupters change hormone levels in humans. • SO reproductive development in males and females of various species including humans may be effected. • For example, DDT in Lake Apopka in Florida in 1980 was followed by male alligators having lower testosterone levels • Some cancers are hormonally reactive, so cancer rates may change/increase. • 60 studies since 1938 report sperm counts from approx. 15,000 men. Over time, the counts have decreased 50% from 1940 – 1990 • 2010 update: PCB’s and DDT suspected.

  31. More terms: • When two or more pollutants’ effects add as you expect when you mix them, they are called simply additive. • When two or more pollutants react in a way that causes a stronger hormone change than either would do alone, we call that synergism. (usually bad) • If the result is less than either alone, then it is called antagonism. (usually good) • This hypothesis was not widely accepted until the 1990’s. Environmental problems can arise from surprising combinations of ‘harmless’ chemicals. Even though a chemical is thought safe, it may not be in every situation.

  32. Invasive Species… • What examples have you heard of?

  33. Invasion of the habitat snatchers • Cargo-carrying ocean vessels carry approximately 79 million tons of ballast water containing foreign clams, mussels, worms, small fish, crabs and microscopic aquatic organisms. • The jellyfish-like organism called a comb jelly hit the Black Sea. With much food and no natural predators, it underwent explosive growth. • Fishing industries have been almost eliminated due to the die-off of native fish populations.

  34. Here at home: • The Zebra mussel from the Caspian Sea hit the Great Lakes in the mid 1980’s. • It clusters on all objects in the water (buoys, boats, and water intake systems). • Now has invaded the Mississippi River • Costs the US about $5 billion to control and in economic losses

  35. Other examples? • Rabbits in Australia (then foxes, then the myxomatosis virus – 90% initially, 75% now)

  36. And… • Kudzu in the Southern US (1876) • Mosquitoes with West Nile virus – eastern US – 1999, 46 states in 2003, all states by 2010 • Wild/feral cats • Weeds: (bermuda grass) in the desert southwest (Georgia in the 1800, spread west during the Gold Rush – 1850’s) • http://www.fws.gov/invasives/

  37. Overview Time… • We’ll spend more time repeating these BIG issues in the next 3 weeks. • (I’m repeating that I’ll be repeating.)

  38. Onto higher topics… Ozone • Stratospheric Ozone • Found in a layer of the atmosphere from 6.2-28 miles up • Formed by ultraviolet rays from the sun breaking down O2 (diatomic oxygen – what you breath) • Shields us, likewise, from this UV light • Protection from sunburns, skin cancer, plant mutations

  39. The hole truth • Thinning NOT a hole • Hypnotized to be caused by chlorofluorocarbons (CFC’s) • First observed in 1985 over Antarctica • Happens Sept/Oct every year – Spring in the southern hemisphere • 1990 amounts of ozone were 50% lower than 1980 amounts. • 1992 some thinning observed over the Arctic

  40. The culprit • CFC’s = a chlorine source  a catalyst • Noclilucent clouds • Colder temperatures up there • From Global Warming? (more heat near the earth surface, less aloft) • 1987 – 160 countries cut back on CFC production/use. • CFC’s can last (a catalyst is not consumed) for 120 years+ • More on this later.

  41. CO2 and Global Climate Warming • A hot topic. (sorry) • More like a thermal blanket than a greenhouse (The Thermal Blanket Effect would be a better name, but Greenhouse stuck). • The atmosphere is transparent to visible light (so we can see stars and the sun) • It is NOT as transparent to infrared light – the way the earth cools itself. CO2 would look like a haze if you ‘saw’ with infrared eyes.

  42. Warming up • So the theory is that more CO2 = more infrared that SHOULD go to space stays down near the earth’s surface. We warm up down here.

  43. Sources- it matters! • Burning forests/grasses = releases CO2 BUT growing trees/leaves/grass consume CO2 • NOT a source of greenhouse warming • Oil/coal = LONG TERM carbon storage – it’s CO2 that hasn’t been up here in a LONG time • This means a new balance needs to be set…

  44. The famous carbon graph

  45. Back in time…