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Global Climate Change. Why focus on this topic?. Should concerns over climate change come to fruition, it will produce more pressure on global economic, social, and political systems than any phenomenon in recorded human history. That is a big IF!! It is also too big to ignore
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Why focus on this topic? • Should concerns over climate change come to fruition, it will produce more pressure on global economic, social, and political systems than any phenomenon in recorded human history. • That is a big IF!! • It is also too big to ignore • This topic is about probabilities, possibilities, and our understanding and responses.
Economic issues • Growth and development are strongly tied to energy consumption. • Trade and trade policy • We can export some pollution to other nations for manufacturing. • Industrial waste, smog, hazardous waste • We cannot ‘export’ global warming – it’s global! • The CO2 China and Russia emit affect us as much as them.
Understanding the problem • Climate change tests our cognitive capacities to understand, act, and innovate. • Belief in the validity of the concerns for the climate may be tied to cognitive processing of information. • If you are closely tied to fossil fuels, the climate change debate is threatening to your survival. • Cognitive dissonance • Selective perception • Information and cognition
Where to stand on this issue? • I strongly suggest you pick a position based on your ability to understand the science, the politics, and the uncertainties that lie with both. • Make your understanding of the issues data driven. • Note that “data driven” includes the data inherent in models – much includes estimates (or data with uncertainty) • You can take any position: • From: Dismiss it as misguided alarmist clap-trap • To: The sky is falling and we are going to die. • Pick your spot on this continuum based on what you understand, not what you want to be.
GCC – The Central Issue • Global Climate change refers to a set of environmental concerns that are related to human activity, primarily • Global warming • The “Ozone Hole” • This Issue, in my opinion, will likely emerge to dominate international relations, directly or indirectly, over the next 20-30 years, for centuries to come.
Global Warming • Global warming refers to the gradual increase of the Earth’s temperature because of energy trapped by the Earth’s atmosphere • The retention of the heat by the atmosphere is called the greenhouse effect.
How the Greenhouse Effect works • Heat, in the form of short wave infrared radiation is received by the Earth from the sun • This heat is reflected back out into space in the form of long-wave infrared radiation. • As long as this energy input-output exchange is in equilibrium, we stay the same temperature (globally) • If something alters it, we either heat up or cool down. • (Greenhouses do not work this way)
Scientific Controversy over the greenhouse effect • There is none. • This is accepted by the scientific community as clearly sound. • It is not theory, it is part of the scientific ‘canon’ • There is, however, concern that the use of the term is inappropriate, since greenhouses don’t trap infrared radiation
Solar Radiance • 11 year sunspot cycle • Other cycles are conjectured, but not confirmed. http://earthobservatory.nasa.gov/Features/ACRIMIII/
Other equilibrating factors • Malinkovitch cycles • Precession: 26,000 year cycle • Elliptical orbit rotation: 21,000 years • Obliquity (angle of plane of elliptic): 41000 years • These do affect temperature, but the analysis is still unclear • They would suggest we may be 6,000 years into a 30,000 year cooling cycle.
Albedo • Whatever the radiance coming in, a significant portion is reflected out • Albedo • Snow cover is important, with highest albedo • Cumulus & stratus clouds have high albedo • Water has a very low albedo
Permanentgases • Permanentgases in the atmosphere by percent are: • Nitrogen 78.1% • Oxygen 20.9% • (Note that these two permanent gases together comprise 99% of the atmosphere) • Other permanent gases: • Argon 0.93% • Neon 0.002% • Helium 0.0005% • Krypton 0.0001% • Hydrogen 0.00005%
Variable greenhouse gases in the atmosphere • Variable gases in the atmosphere and typical percentage values are: • Water vapor 0 to 4% • Fluctuates substantially, daily and seasonally • Resident in atmosphere ~9 days • Carbon Dioxide 0.039% • Resident ~ 50% lasts about 1 century - GWP set to 1 • Methane 0.0002% • Resident 12 years, GWP = 72 over 20yrs – decays to CO2 • Ozone 0.000004% • CFC’s (not naturally occurring) • Resident 100yrs, GWP=11000.
Relative concerns over Greenhouse gases • CO2 is the largest concern, being the largest greenhouse gas constituent of the atmosphere • Methane holds more heat, but because it is chemically more active, its atmospheric duration is about 12 years • CFC’s hold much more heat, and last a very long time, but still are a smaller portion • Also being reduced due to Montreal protocol
Atmospheric CO2 • Atmospheric CO2 is believed to have been about 280 ppm (parts per million) in the pre-industrial age. • This figure is based on estimates of carbon sinks and flux, along with the geological record. (ice core samples, bubbles in amber, etc)
CO2 • The most plentiful greenhouse gas • Results from • Burning of vegetation/deforestation • Reduced uptake in plants/deforestation • Combustion of fossil fuels • Gas is the best fuel (e.g. CH4) • Oil is medium CO2 source (e.g. C8H18) • Coal is the worst • Based on ratio of carbon to hydrogen in the molecules • Coal is 60-91% carbon, by weight
Mauna Loa CO2 observations • The data on atmospheric CO2 collected by Keeling at the Mauna Loa observatory is said to be the most widely seen data set in the world. • It was started in 1955 • CO2 was at 313ppm then. • It is at 388.92ppm now (October 2011), an increase of 24% in 56 years. • Source: http://www.esrl.noaa.gov/gmd/ccgg/trends/#mlo_full
Can this be natural? • The climate change debate has shifted to: • Is it anthropogenic? • Could this change be natural, just like the Ice Age’s? • The answer is: Possible, but not likely. • The observed change in atmospheric CO2 seems to not correlate to any observable phenomena.
Has it ever been this high? Source: NASA: http://climate.nasa.gov/evidence/
Carbon Sources and Sinks • Places that provide carbonare called reservoirs. • Places where carbon settles are called sinks • Exchanges between sinks and reservoirs are called fluxes. • There are four major reservoirs for carbon • The atmosphere • The oceans • The biosphere • Fossil fuels • Ultimately the crust forms the basic sink for carbon via the deep oceans to carbonate rock and fossil fuels
Carbon Dioxide • Primary source is combustion of fossil fuels • Global Coal Production - >7B metric tons • Total Fossil Fuel Production - • Other Sources • Manufacturing • Propellants • Us –about 2.3 lbs of CO2 daily (= 2.9B tons/yr) • BTW: Volcanoes–up to about 250 million tons/year
Methane • Sources • Coal mining • Natural Gas extraction and transportation • Oil production • Animal digestion • Deforestation (incomplete combustion) • Organic decomposition • Thawing tundra / peat bogs • Resident in atmosphere about 12 years
CFCs • Nasty little gases – only anthropogenic • CFCs do not occur in nature – the Fluorine bond is too strong to break naturally. • CFCs come from • Refrigerants • Styrofoam, foaming agents • Cleaning electronics • Spray propellants • Being phased out due to the Montreal Protocol
Water Vapor • Water vapor residence time is very brief and highly variable. • Especially seasonally. • Water vapor content affects cloud cover. • Temperature rise (or fall) can influence cloud cover.
Environmental Impacts of Climate Change • Temperature rise • Precipitation • Extreme precipitation events • Flooding • Droughts • Tropical storms • Soil Moisture • Changing Habitats • Reduced glaciation/snow cover/ice • Sea Level Rise • Ocean acidification
Temperature Rise • Estimates are in the 1.5° to 4.5° C range based on General Circulation Models (GCM) of the atmosphere. • Every degree C is equal to about 100 miles of latitude. • This means that WV will have the ecosystems of North GA/SC • Rising temperature means rising AC usage, which means rising CO2 consumption, accelerating greenhouse effect • This is a positive feedback loop
“ClimateGate” • The December 2009 East Anglia email controversy • Hacked emails revealed some information that ranges from disconcerting to silly – depending on your beliefs. • The data • The Briffa reconstruction • This is what has people upset – the green is the real data • (see http://wattsupwiththat.com/2009/11/28/how-the-trick-was-pulled-off/ )
The tree ring (dendrochronology) data • This is the raw data with the red data being the 1961-present data deleted
What does it mean • The Post 1961 tree ring data was dropped. • The scientists felt it was “incorrect” • While we often have such reasons, never omit data without full justification! • The actual “Instrumental” data was added to the tree ring data for the suspect years 1961-present. • This is not good scientific practice! • It does not call into question any of the other science • Like…
What about this Winter? • Do not think locally – and the US is “local”
The BEST Project • Berkeley • Noted Climate Change skeptic Richard Muller • Highly regarded UC Berkeley Physics prof • Challenged the science of climate change • Received a grant funded by Koch brothers • Here what he just concluded: • BEST temperature record