Lecture: Greenhouse Gases

Global warming and Sustainablity

What is the connection? Why talk about it? Science of Global Warming: How is the Earth heating up, and how do humans cause most of it?  

When we were doing the environmental movements, we were concerned about protecting open spaces for human enjoyment. Barton Springs: aquifer caused pollution An urbanized watershed would cause Barton Springs to become an algae habitat Preserving greenbelts/Green spaces Sustainability wasn't a word yet, environmentalism was the word back way then

In the late 70s, early 80s, scientists started asking questions. How did people become aware of Global Warming? increase in temperature - Glaciologists documented receding Glaciers Greenhouse Gases are naturally occurring gases that keep heat on Earth. Too much is BAD. But we still need some for survival. By mid-late 90s scientists agreed humans were emitting: Carbon Methane Nitrous (Actually there are seven but these are the worse)

How did we get to sustainability?

More heat is kept within Earth than is released....sooooooo Warmer Gulf waters can fuel Hurricane power In the future expect stronger extreme weather (NOT MORE...JUST STRONGER) Changes to new habitats will be so fast, that animals cannot adapt. This means an extreme kill off of animal species. Speed is another key of Global Warming Humanity will have the same issue:  

What are the Consequences?

If we keep heating up our Earth, then crop failure occurs. People who depend on agriculture will have to migrate. Poor People will suffer the most. Places become no longer suitable for living, so migration occurs. Loss of shelter Culture tensions Environmental issues become Economic Issues The Pentagon  Threat assessment every 10 years: What is the biggest threat to National Security? 2000-2010 assessment found it to be Global Warming.... This is because migration = social conflict  

Leads to Migration

Sustainability Extremes

    richer countries will simply lose ability to claim resources, whereas poorer countries will actually have less chances of survival

Energy = radiation Heat is how we feel that (solar) radiation Radiation = Energy = Heat some radiation is reradiated albedo - just a measurement of how much radiation is bounced back Occurs at the molecular level. ice - reflects radiation  (high albedo) water - absorbs radiation (low albedo) cloud cover - reflects radiation Feedback mechanism - reversing the albedo of an object Feedback loop - the repetition of the feedback mechanism    

Physics of the Phenomena

melting sea ice = higher sea levels If Greenland melts, then sea will rise 10ft. West Coast cities aren't at as much risk, they are basically on mountains.... just look it up, observe what areas will go under and who will survive

TOO MUCH WATER

Carbon Cycle

Carbon exists in the atmosphere. Trees eat carbon, when they die they emit carbon. dead trees go underground. Ocean water absorbs more than it emits. carbon goes into fishes. Fish need carbon to strengthen their bones. dead fish bones get buried. All of this carbon eventually gets way down below the surface and creates coal/oil. Humans take this carbon and use it for energy. This increase how much carbon is released into the air. Carbon bank - Carbon storage About 75% of greenhouse gases we release are carbon gases   

...how to fix it....

    STOP PUTTING CARBON IN THE AIR

Methane (quick note)

Cow farts/burps release methane = greenhouse gases NOOOOO it is not their fault!!!  

By 1950, Carbon emissions become extreme Because of agriculture, animal/crop production contributed to greenhouse gases Industrial Revolution -----> Globalization -----> industry causes extra emissions There is a delayed effect on carbon, you need a certain amount to create a greenhouse effect. So as more carbon is released into the floating Carbon bank, the effects become more noticeable.  

When did it a problem?