Climate and climate change
Download
1 / 37

Climate and Climate Change - PowerPoint PPT Presentation


  • 89 Views
  • Updated On :

Climate and Climate Change. Climate is what you expect and weather is what you get. Green Bay 1977-2002. Green Bay 1887-2002. Green Bay 1887-2002. Green Bay 1887-2002. Long-Term Trends. Long-Term Trends. Long-Term Trends. Long-Term Trends. Long-Term Trends. Some Conclusions.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Climate and Climate Change' - catalina


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript











Some conclusions l.jpg
Some Conclusions

  • This is not as easy as the media make it seem

  • The fact that it’s not easy doesn’t excuse us from dealing with it

  • The fact that something can’t be proven conclusively doesn’t protect you if you make the wrong decision

  • Don’t confuse reasoning with reality




Positive and negative greenhouse effects l.jpg
Positive and Negative Greenhouse Effects

Positive Greenhouse Effect

  • Light enters

  • IR trapped: Warming

    Negative Greenhouse Effect

  • Light Blocked

  • IR can leave: Cooling

  • Titan


Greenhouse gases l.jpg
Greenhouse Gases

  • Water Vapor

  • Carbon Dioxide

  • Methane

  • Nitrous and Nitric Oxides

  • Ozone

  • Transparent to visible light but absorb infrared




Carbon dioxide l.jpg
Carbon Dioxide

  • Has doubled to 350 ppm since start of Industrial Revolution

  • Coupled to Temperature Rise?

  • More Cloud Cover?

  • Taken up by biomass?

  • Taken up by oceans?


Paleoclimatology l.jpg
Paleoclimatology

  • The present is the key to the past – but

  • The past is also the key to the present

  • Study of ancient climates

  • Have to rely on proxy measurements

  • How to convert qualitative data to numbers?


Ancient paleoclimatology l.jpg
Ancient Paleoclimatology

  • Oxygen 18

  • Fossils

  • Evaporites

  • Glacial Indicators

  • Air bubbles in amber


Earth s climatic history l.jpg
Earth’s Climatic History

  • Faint Early Sun

  • Anoxic Atmosphere

  • Advent of Life – UV Protection?

  • 2.3 by Glaciation

  • 2 b.y. Oxygen Threshold

  • End of Iron Formations

  • First Red Sandstones

  • Snowball Earth


Earth s climatic history23 l.jpg
Earth’s Climatic History

  • Cambrian Explosion

  • Ordovician Ice Age

  • Advent of Forests

  • Permian Ice Age

  • Cretaceous Warm Period

  • Eocene Warm Period

  • Pleistocene Ice Age


Recent paleoclimatology l.jpg
Recent Paleoclimatology

  • Historic Records

  • Tree Rings

  • Pollen Studies

  • Oxygen 18

  • Ice Cores


Holocene climate l.jpg
Holocene Climate

  • 11,000 Younger Dryas Cooling

  • 9,000-6,000 Mid-Holocene Warm Period (“Climatic Optimum”)

  • 900-1300 AD – Medieval Warm Period

  • 1300-1450 Little Ice Age I

  • 1450-1550 Recovery

  • 1550-1800 Little Ice Age II


Effects of global warming l.jpg
Effects of Global Warming

  • More Heat Extremes

  • Drought

  • Rise in Sea Level

  • Temporary Severe Cold Spell?

  • Rapid Migration of Ecological Zones

  • More Biomass but Lower Nutritional Value


Not a bad thing l.jpg
Not a Bad Thing?

  • Reduced Energy Demands

  • Longer Growing Seasons

  • More Biomass

  • More Habitable Land


Ozone l.jpg
Ozone

Stratosphere – Good

  • Absorbs solar ultraviolet

    Troposphere – Bad

  • Toxic

  • Contributes to air pollution


Ozone depletion l.jpg
Ozone Depletion

  • Cl stripped off synthetic molecules by solar ultraviolet

  • Cl reacts with ozone, acts as catalyst

  • Cl – CF3 (Freon) 360

  • Cl – CCl3 (Carbon tetrachloride) 294

  • Cl – H (Hydrochloric Acid) 431




Long term climatic trends l.jpg
Long-Term Climatic Trends

  • Brightening of the Sun

  • Capturing of CO2 by carbonate rocks?

  • Moist greenhouse effect

  • Runaway CO2 Greenhouse Effect

  • Venus conditions


The goldilocks problem l.jpg
The Goldilocks Problem

  • Venus is too hot

  • Mars is too cold

  • Earth is Just Right


Planetary habitable zones l.jpg
Planetary Habitable Zones

  • Primarily in the Liquid Water Zone

  • Can’t be too warm

  • Water Vapor in upper atmosphere broken down by solar UV and charged particles (photodissociation)

  • Hydrogen escapes to space


The ultimate long term forecast l.jpg
The Ultimate Long-Term Forecast

  • Slow warming trend for the next billion years

  • Increasing humidity

  • CO2 decrease leads to extinction of plants?

  • Boiling and evaporation of the oceans



The oreo model of life history l.jpg
The Oreo Model of Life History

  • Micro-organism Earth (0-3 billion years)

  • Multicellular Earth (3-5 billion years)

  • Micro-organism Earth (5-6 billion years)

  • “The white creamy middle”