a different perspective on climate change john r. christy university of alabama in huntsville...
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A Different Perspective on Climate Change
John R. ChristyUniversity of Alabama in Huntsville
Alabama State Climatologist
Consensus is not Science
William Thompson (Lord Kelvin)
All Science is numbers
Michael Crichton
Some people will do anything to save the Earth ...
except take a science course.
Greenhouse “Affect”, Rolling Stone
P.J. O’Rourke
Energy Technology1900: World supported
56 billion human-life years
2005: World supports 429 billion
human-life years
The Basic Numbers
• Carbon Dioxide has increased 35%• Global Surface temperature rose
0.7 °C in past 100 years• Surface temperature responses to
2xCO2 increases (alone) is ~ 1 C• The associated feedbacks are
where the uncertainties are large (i.e. no confident numbers)
The Basic Numbers• Humans produce about 7
gigatons of CO2 (carbon mass) per year from energy production
• About 3.5 gigatons accumulates in the air each year
• There are about 740 gigatons of CO2 in the atmosphere
• The rate is increasing around 0.5% per year
The Basics
• Climate is always “changing”– Global temperature is rising or
falling– Sea level is rising or falling– Glaciers are retreating or
advancing
The Basics• Climate is always “changing”
– Global temperature is rising or falling– Sea level is rising or falling– Glaciers are retreating or advancing
• Climate cannot be adjusted in a predictable way– Initiatives to control climate have no
dependable outcome– Initiatives proposed to date have such a
tiny impact on the overall emissions, we could not measure any direct effect
"Global" Surface Temperature HadCRUT3
-0.8
-0.6
-0.4
-0.2
0.0
0.2
0.4
0.6
1850 1870 1890 1910 1930 1950 1970 1990 2010
Christy et al. 2006, J. Climate
+ Valley Stations•Mountain Stations
•Christy et al. 2006, J. Climate
CA Valley and Sierra (Jun-Nov) 1910-2003
8
12
16
20
24
1910 1920 1930 1940 1950 1960 1970 1980 1990 2000
°C
Valley TMax (- 10°C)Valley TMinSierra TMin
Christy et al. 2006
MODIS21 Jul 2002
Jacques DescloitresMODIS Land Rapid Response Team NASA GSFC
Snyder et al. 2002
Sierras warm faster than Valley in model simulations
SE Surface Temperature Trend 1895-2003
-0.05
0.00
0.05
0.10
0.15
Obse
rved
BCM_C
M1
CCCMA_C
GCM
3
CCCMA_C
GCM
3_T63
CSIRO
_MK3_
0
GFDL_C
M2_
0
GFDL_C
M2_
1
IPSL_C
M4
MIR
OC3_
2_HIR
ES
MPI_
ECHAM5
MRI_
CGCM
2_2A
K/D
ecad
e
What About Upper Air Temperatures?
What About Upper Air Temperatures?
• Recent media reports suggest the upper air temperature record is in agreement with the surface and with climate models, so global warming theory must be right
• IPCC AR4 more or less supports this view
• Discrepancies, however, still exist though not communicated in the media
Vertical Temperature Change due to Greenhouse Forcing in
Models
Model Simulations of Tropical Troposphere Warming:About 2X surfaceLee et al. 2007
Christy and Norris 2006,Christy et al. 2007
Christy and Norris 2006,Christy et al. 2007
-0.6
-0.4
-0.2
0.0
0.2
0.4
0.6
0.8
1.0
1978 1982 1986 1990 1994 1998 2002 2006
Global Bulk Atmospheric TemperaturesUAH Satellite Data
Warming rate 60% of model projections
Cold Places?
Antarctica Sea Ice
Chapman, U.Illinois
Antarctica snowaccumulationtrends cm/yr
1992-2003
Davis et al. 2005
See also:Monoghan et al 2006Van de Berg et al. 2006
Schneider et al. 2006
AntarcticaThermometersIce Cores
Doran et al. 2002
Antarctica Temperature VariationsIsotopes (green, Schneider et al. 2006), Thermometers (blue,
HadCRUT3)
-0.6-0.5-0.4-0.3-0.2-0.10.00.10.20.30.40.5
1800 1850 1900 1950 2000
°C D
epar
ture
s fr
om A
ver
age
Arctic Sea Ice
Chapman, U.Illinois
North Polar RegionsTemperature HadCRUT3
-5
-4
-3
-2
-1
0
1
2
3
1850 1880 1910 1940 1970 2000
Arctic 70-85NGreenland
Satellite Sea Ice Record
Greenland Summer Temperatures
Vinther et al. 2005
3
4
5
6
7
8
9
1780 1800 1820 1840 1860 1880 1900 1920 1940 1960 1980 2000
JJA11-Year Avg
Greenland Borehole TemperatureDahl-Jensen et al. 1998
-32.5
-32.0
-31.5
-31.0
-30.5
0 500 1000 1500 2000
AlaskaHadley CRU 3 (°C)
Shift in 1977, but high natural variability
-4
-3
-2
-1
0
1
2
3
4
1900 1920 1940 1960 1980 2000
Kilimanjaro 18OTemperature Proxy Thompson 1996
6
7
8
9
10
11
12
13
14
1600 1700 1800 1900 2000
NIF2NIF3SIF2SIF1Mean N,S
When Hemingway writes “Snows of
Kilimanjaro”—half of the “snows” are
already gone
X
-5
-4
-3
-2
-1
0
1
2
3
4
1955 1965 1975 1985 1995 2005
Arusha/Kilimanjaro
TMax
Extreme Weather?
Oklahoma - record long period (> 100 days) without a tornado 2003-04
US Hurricanes
U.S. Hurricane Strikes by Decade (NOAA 2007)
0
5
10
15
20
25
1850 1870 1890 1910 1930 1950 1970 1990 2010
Last year of Decade
Cat 1-5Cat 3-5
2001-2006
Global Hurricane ActivityThere has been no significant change in
global net tropical cyclone activity (Klotzbach 2006)
Droughts? US: Blue = Fewer and Shorter
Andreadis and Lettenmairer 2006
Sea Level Rise?
Global Sea Level (gsl) elevation (mm) and growth rate (mm/yr) - Jevrejeva et al. 2006
Suzuki et al. 2005+ Thermal Expansion+ Greenland melting- Antarctica accumulation
Neptune warming?
(a) represents the corrected visible light from Neptune from 1950 to 2006; (b) shows the temperature anomalies of the Earth; (c) shows the total solar irradiance as a percent variation by year; (d) shows the ultraviolet emission from the Sun (Source: Hammel and Lockwood (2007)).
Evidence Thus Far• Global surface and atmospheric
temperatures are rising in a way somewhat inconsistent with model projections of greenhouse gas forcing
• Overall decline in ice mass, with sea level rise of 1” per decade
• Severe weather not becoming more frequent
Two Sides?
• Al Gore’s An Inconvenient Truth– Disaster is upon us
• Channel 4’s The Great Global Warming Swindle– Mankind has no impact on
climate
• Is either of these the truth?
Main Point:
I don’t see a disaster developing
But, suppose you do ….
Model Projection of Global Temperature
0.0
0.5
1.0
1.5
2.0
2.5
3.0
1990 2005 2020 2035 2050 2065 2080 2095
°C
A1BA1B USA AB 1493
The IPCC AR4 best guess scenario (A1B, red) and the application of California AB 1493 (green) auto emission regulation to all states (0.01 °C)
Model Projection of Global Temperature
0.0
0.5
1.0
1.5
2.0
2.5
3.0
°C
A1B1000 nuclear power plants
The IPCC AR4 best guess scenario (A1B, red, global temperature) and the impact of 1000 nuclear power plants operating by 2020 (green)