Transcript Anthropogenic Global Warming? Beyond CO2 - meteoLCD

Anthropogenic Global Warming
Reality or Fiction?
Version 1.1 06Sep08
Francis Massen
Physics Lab, LCD and meteoLCD
Lycée Classique de Diekirch
http://meteo.lcd.lu
[email protected]
August 2008
Index
•
•
•
•
•
•
•
•
•
•
Climate and weather
Climate metrics
Climate models
Causes of climate change
How good are the data and the models?
IPCC and the so-called consensus
The skeptics and their arguments
Major scares, real or imagined?
Cooling down?
Conclusions
AGW.. reality or fiction?
2
Climate and weather
• Weather = actual state of the
atmosphere, chaotic changes
• Climate = mean state ( min. 30 years) of
the atmosphere together with its
statistical variations
Extreme events are a “normal” feature of
every climate
Climate is always changing… it never is
or was constant!
AGW.. reality or fiction?
3
Pielke, Colorado University, 2008
The Earth’s climate system is highly
nonlinear: inputs and outputs are not
proportional, change is often episodic and
abrupt, rather than slow and gradual, and
multiple equilibria are the norm
AGW.. reality or fiction?
4
The motor of the weather
• Sun = engine that drives weather/climate
• Uneven heating by the sun of the globe
causes heat flow from hot to cold regions
(through convection: air movements and
ocean circulation, complicated by the
rotation of the globe)
AGW.. reality or fiction?
5
Climate change is caused by
•
•
•
•
Variable inclination of earth axis
long-time
Variable distance earth/sun
Variable sun activity (TSI, UV and magnetic)
Variable galactic cosmic rays
______________________________
• Changes in land usage and land cover
• Changes in the composition of the atmosphere
(natural, anthropogenic)
short time
AGW.. reality or fiction?
6
Climate metrics
• Global temperature (in °C) measured by
surface weather stations, balloons and
satellites (MSU, since 1978)
• Ocean heat content (in J) measured by
ships, moores,…, floating buoys (Argo,
since 2003)
AGW.. reality or fiction?
7
Global temperature
• Not many good long-time measurements
(instruments only since ~1750)
• Past temperatures must be infered from
proxies (tree rings, isotope ratios in ice
cores and sea-shells)
• Results often dubious and uncertain
• Meaningful? (no uniform temperature)
AGW.. reality or fiction?
8
What was commonly assumed
(IPCC SAR, 1995)
AGW.. reality or fiction?
9
The Hockey Stick (MBH 98)
IPCC SAR 2001 [1]
No Medieval
Warm Period !
No Little Ice Age !
AGW.. reality or fiction?
10
The Hockey Stick (MBH 98) [2]
• Mann, Bradley, Hughes: temperature profile of
middle age essentially derived from a couple of
bristlecones
• Dubious statistics
• IPCC TAR 2001 icon, published many million
times
• Demolished by McIntire/McKitrick (2003)
• Embarrassment for the IPCC (not anymore in
4AR, 2008)
AGW.. reality or fiction?
11
The Hockey Stick (MBH 98) [3]
• Ian Jolliffe, expert statistician, 2008:
“It therefore seems crazy that the MBH
hockey stick has been given such
prominence and that a group of
influential climate scientists have
doggedly defended a piece of dubious
statistics. “
AGW.. reality or fiction?
12
The Hockey Stick (MBH 98) [3]
Loehle reconstruction, not using tree rings (2007):
Medieval warm
period (MWP)
AGW.. reality or fiction?
13 (LIA)
Little Ice Age
Divergence problem [1]
• Recent tree rings derived temperatures are lower
than measured ones!
measured
AGW.. reality or fiction?
tree
ring
14
Divergence problem [2]
Wilson, GRL, 2007:
No current tree ring (TR) based reconstruction of extratropical Northern
Hemisphere (ENH) temperatures that extends into the 1990s captures the
full range of late 20th century warming observed in the instrumental record
Wilmking, 2008:
This "divergence effect" seriously questions the validity of tree-ring based
climate reconstructions
AGW.. reality or fiction?
15
Recent temperature data sources
• Surface:
GISTEMP (GISS, Nasa) [Hansen]
NCDC (US)
Hadley(GB) [Jones]
• Satellites:
MSU = microwave sounding unit
UHA (US) [Christy, Spencer]
RSS (US) [Mears]
AGW.. reality or fiction?
16
Surface temperatures heavily
adjusted for UHI, instrument drift,…
AGW.. reality or fiction?
17
One of many problems: land-based station dropout
(NOAA: GHCN) favours urban stations
(UHI problem)
AGW.. reality or fiction?
18
[icecap]
Hadley 1850 to 2007
Similar warming rate
very different CO2 increase
dCO2=+43 ppm
dCO2=+17ppm
AGW.. reality or fiction?
19
[climate4you]
El Nino 1998
Last 40 years…
See difference!
AGW.. reality or fiction?
[climate4you]
No GW since202001 !
Global temperature = bad metric?
Prof. Roger Pielke, Sr
University of Colorado, Boulder:
Global temperature is not a correct metric for climate change.
Ocean heat content is the metric to be used.
AGW.. reality or fiction?
21
Barnett [Science, 2001]
Observations (dubious?)
AGW.. reality or fiction?
22
Decreasing global temperatures
Willis [GRL, 2004]
upper 750m
AGW.. reality or fiction?
23
Hansen [Science, 2005]
The observed annual mean rate of ocean heat gain
between 1993 and mid-2003 was 0.86 +/- 0.12 W/m2 per
year for the 93.4% of the ocean that was analyzed.
AGW.. reality or fiction?
24
Argo floater system (starting 2003)
AGW.. reality or fiction?
25
Argo floaters in use
AGW.. reality or fiction?
26
Argo results [Willis, JPL, 2008]
Decreasing ocean heat content!
AGW.. reality or fiction?
27
GHG and climate forcing
• GHG’s (water vapour, CO2,
methane,….) absorp a portion of the
outgoing long wave radiation and radiate
it back to the surface
• Earth heats up until a new equilibrium
(incoming radiation = outgoing radiation)
is reached
• Without GHG’s, earth would be at -18°C
instead at +15°C
AGW.. reality or fiction?
28
GHG contribution to natural GH
AGW.. reality or fiction?
29
Climate forcing F
• F = hypothetical increase in TOA
irradiance caused by a change of [CO2]
relative to pre-industrial times (280ppm)
• F = 5.35*ln(actual_CO2/reference_CO2)
(Arrhenius law, 5.35 from [Myrhe, 1998])
• F = 3.7 Wm-2 for CO2 doubling
F = 1.7 Wm-2 today (280 → 385 ppm)
The factor 5.35 is derived from historical surface temperatures, and may
be grossly overestimated! [Erren, 2002]
TOA = Top Of Atmosphere
AGW.. reality or fiction?
30
If the earth was a black body…
• Stefan-Boltzmann: F = σT4
σ=5.67*10-8
• dF/dT = 4σT3 and dT =1/(4 σ)*dF/T3
• With T = 15°C and dF=3.7 as previous
gives dT = 0.68°C for a CO2 doubling
and dT = 0.31°C for today
AGW.. reality or fiction?
31
Climate sensitivity λ (earth ≠ black body)
• dT = change in global temperature
caused by given change in forcing dF
• dF = λ*dT or λ = dF/dT [Wm-2K-1]
• dT = dF/ λ without feedbacks
• dT = dF/ (λ-f1-f2..) with feedbacks
f > 0 positive feedback (e.g. water vapour)
f < 0 negative feedback (e.g. cloud cover )
AGW.. reality or fiction?
32
The data [Spencer, 2008]
Climate sensitivity
dT for doubling CO2 (from 280 to 560ppm): dT = 3.7/4.5 = 0.8 °C
AGW.. reality or fiction?
33
The IPCC
• IPCC = political organisation (UNEP, WMO)
• Evaluates scientific literature and research and
issues AR’s (assessment reports):
1990:FAR 1995:SAR 2001:TAR 2007:4AR
• Authors often are their own reviewers
• With each AR comes a SPM (summary for
policy makers) written by bureaucrats and
political delegates (not scientists!)
• AR’s had to be changed to conform to the SPM
published before the AR’s !
AGW.. reality or fiction?
34
IPCC = 2500 scientists?
Most important reports = ~50 authors
Mc Lean, 2008: “Prejudiced authors, prejudiced findings”:
..two of Hadley’s Centre’s contribution authors (Jones and Thorne) were among
the reviewers of the chapter that they had themselves written…
…the majority of scientists who are skeptical of a human influence significant
enough to be damaging were unrepresented…
AGW.. reality or fiction?
35
IPCC and climate models
• IPCC relies heavily on anthropogenic GHG
emissions and climate models
• IPCC uses scenarios (which are not predictions
[Trenberth, IPCC author])
• IPCC scenarios emphasize role of CO2
emissions, neglect LULC and solar influence
(LULC = Land Use Land Change)
• SPM’s ignore the poor LOSU of many forcings
(LOSU = Level Of Scientific Understanding)
AGW.. reality or fiction?
36
IPCC 4AR scenarios (2007)
AGW.. reality or fiction?
37
( Change relative to pre-industrial 1750 situation)
IPCC forcings (4AR, 2007)
LOSU =
level of scientific
understanding
high
low
AGW.. reality or fiction?
38
Are the models reliable? [1]
[Akasufo, 2007]
hindcast by model
observation
Vast difference between reality and model!
AGW.. reality or fiction?
Akasufo: former director of the International Arctic Research Center
39
Are the models reliable? [2]
[Freeman Dyson]
Freeman Dyson: FRS, physics professor at Princeton University
AGW.. reality or fiction?
40
IPCC critics [1a]
• Dr. Richard S. Lindzen,
Alfred P. Sloan professor of meteorology
at the Massachusetts Institute of Technology:
The IPCC process is driven by politics rather
than science.
It uses summaries to misrepresent what
scientists say.
AGW.. reality or fiction?
41
IPCC critics [1b]
It uses language that means different things to scientists
and laymen.
It exploits public ignorance over quantitative matters.
It exploits what scientists can agree on, while ignoring
disagreements, to support the global warming agenda.
And it exaggerates scientific accuracy and certainty and
the authority of undistinguished scientists.
AGW.. reality or fiction?
42
IPCC critics [1c]
The "most egregious" problem with the IPCC's forthcoming
report, is that it is presented as a consensus that involves
hundreds, perhaps thousands, of scientists . . .
and none of them was asked if they agreed with anything in
the report except for the one or two pages they worked on.
AGW.. reality or fiction?
43
IPCC critics [2]
• Prof. Roger Pielke Sr.
University of Colorado in Boulder
The IPCC is an oligarchy that is using its
privileged position to advocate for a
particular perspective on the role of humans
within the climate system.
• Oligarchy = form of government in which all power is
vested in a few persons or in a dominant class or clique
AGW.. reality or fiction?
44
IPCC critics [3]
• House of Lords, “ The Economics of Climate
Change”, 2006:
It seems to us that there remains a risk that the
IPCC has become a “knowledge monopoly” in
some respects, unwilling to listen to those who
do not pursue the consensus line.
AGW.. reality or fiction?
45
Consequences of global warming:
there remains no phenomen that is not caused or influenced
by GW!
A complete list of things caused by global warming
Acne, agricultural land increase, Afghan poppies destroyed, Africa
devastated, Africa in conflict, African aid threatened, African summer frost,
aggressive weeds, air pressure changes, Alaska reshaped, Agulhas current
moves, Alps melting, Amazon a desert, American dream end, amphibians
breeding earlier (or not), anaphylactic reactions to bee stings, ancient forests
dramatically changed, animals head for the hills, Antarctic grass flourishes,
Antarctic ice grows, Antarctic ice shrinks, Antarctic sea life at risk, anxiety
treatment, algal blooms, archaeological sites threatened, Arctic bogs melt, Arctic
in bloom, Arctic ice free, Arctic ice melt faster, Arctic lakes disappear, Arctic
tundra to burn, Arctic warming (not), Atlantic less salty, Atlantic more
salty, atmospheric circulation modified, attack of the killer jellyfish, avalanches
reduced, avalanches increased, Baghdad snow, Bahrain under water, bananas
grow, barbarisation, beer shortage, beetle infestation, bet for $10,000, better
beer, big melt faster, billion dollar research projects, billion homeless, billions face
risk, billions of deaths, bird distributions change, bird loss accelerating, bird
visitors
birds confused, birds return early, birds driven north,…
AGW.. drop,
reality or fiction?
46
[http://www.numberwatch.co.uk/warmlist.htm]
Climate change research $$$
• USA:
$37 billion US$ to climate change-related activities
since 2001
• EUROPE:
6th Framework 2002-2006:
2.0 billion Euro
7th Framework 2007-20013: 9.0 billion Euro
plus additional funding of
3.6 billion Euro
• AUSTRALIA, 2008:
$2.3 billion US$ over four years for climate
research
Lindzen: “The research and support for research depends on the alarm”
AGW.. reality or fiction?
47
Dr. Gerd R. Weber
Max Planck Institute, 1992
• “Heute werden auf eine Weise
Forschungsgelder verteilt und Berichte
geschrieben, dass sich daraus eine positive
Rückkopplungsschleife bildet, die allen
Beteiligten Gewinne abwirft. Die
Wissenschaftler bekommen mehr
Forschungsgelder, die Medien neue
Empörungsgeschichten..., den Politikern
erschliesst sich ihr Stimmenpotential."
Gerd R. Weber: Treibhauseffekt. Böttiger Verlags GmbH
AGW.. reality or fiction?
48
The major scares, real or imagined?
•
•
•
•
Melting of glaciers and polar ice
Sea level rising
Hurricanes on increase
Drought on increase
AGW.. reality or fiction?
49
Mont Blanc ice cap
Vincent et al. , JGR, 2007:
“The most striking features of
these figures are the small
thickness changes observed over
the 20th century. … thickness
variations do not exceed ±15 m.
The average changes are +2.6 m
at Dôme du Goûter and -0.3 m at
Mont Blanc. Considering the
uncertainty interval, i.e., ±5 m, it
can be concluded that no
significant thickness change is
detectable over most of these
areas”
World Climate Report
AGW.. reality or fiction?
50
Greenland ice
NOAA: Arctic Report Card 2007
Surface mass balance
~constant.
Other sources: +11 Gt/year
Greenland's temperature record shows that the warmest year on record
was 1941 while the warmest decades were the 1930s and 1940s
AGW.. reality or fiction?
51
Arctic sea ice [1]
-10 %
[NOAA]
AGW.. reality or fiction?
52
Arctic sea ice [2]
• Polyakov (Uni. of Alaska, Fairbanks):
Observations over the last 135 years show that
the recent decrease is within the limits of
natural variations since the 18th century.
The natural low frequency oscillation (LFO, 5080 years) related to fluctuations of the
thermohaline circulation has a strong impact on
ice variability.
AGW.. reality or fiction?
53
Antarctic: ice balance (from satellite)
Wingham et al., University College of London, 2003: ice balance = [27 +/- 29 Gt/y]
AGW.. reality or fiction?
54
Global sea level [1]
~250 mm
Gauges: 2.4 mm/y
Satellite: 2.6 mm/y
(Topex/Poseidon)
[Jevreshava, JGR, 2006]
AGW.. reality or fiction?
55
Global sea level [2]
• Domingues et al, Nature, 2008:
“…previously estimated rates for the
1990s had a positive bias as a result of
instrumental errors…”
“…updated estimate of near-global mean
sea-level rise: 1.6 ± 0.42 mm/year for
1950 to 2003”
AGW.. reality or fiction?
56
Global sea level [3]:
sea level change is not uniform!
AGW.. reality or fiction?
57
[Accuweather]
Hurricane frequency increase? [1]
Hurricane in the eastern Pacific (Englehart, GRL, 2008): trend is negative!
AGW.. reality or fiction?
58
Hurricane frequency increase? [2]
US landfall hurricanes (Wang & Lee, GRL, 2008): trend is negative!
AGW.. reality or fiction?
59
Hurricane intensity increase? [3]
[Swanson, GRL, 2007]
Variable intensity, no trend!
AGW.. reality or fiction?
60
Increasing Drought ? [1]
NPP change 1982-99
AGW.. reality or fiction?
NPP = net primary productivity [kgC/m2]
[Simmon, Nasa]
61
Increasing Drought ? [2]
[Ollson, encyclopedia of earth]
1982-99: NDVI increases…the Sahel is greening!
AGW.. reality or fiction?
NDVI = normalized difference vegetation index, measured by satellite
62
Outlook: cooling down?
• Several recent changes point to a future cooler,
not warmer climate
• There has been no warming since at least
2001, despite rising atmospheric CO2
• Sun activity is unusal low, Aug08 was the first
month since 1913 without any sunspots
• Solar cycle 24 is late, and is predicted to be
calm (idem for SC 25)
AGW.. reality or fiction?
63
Cooling down? [temperature & CO2]
• Global temperature and CO2
1970 – 2000
only period where
dCO2 ~ dT
> 2000:
CO2 rising,
temperature
decreasing
AGW.. reality or fiction?
64
Cooling down? [temperature & CO2]
AGW.. reality or fiction?
65
[icecap]
Cooling down? [temperature & water vapour]
• Satellites show lower troposphere cooling;
atmospheric water vapor trend is negative
AGW.. reality or fiction?
66 2008]
[NOAA,
Cooling down? [permafrost]
• Alaska
Permafrost temperature
remains constant!
[Akasofu, 2008]
AGW.. reality or fiction?
67
Cooling down? [sunspots]
• Sunspot number and global temperature
There
have been more sunspots since the 1940s than at any
AGW.. reality or fiction?
68
other period (of same duration) in the past 1150 years [New Scientist, 2003]
Cooling down? [magnetic activity]
• Sun activity increased dramatically over
last century, but now is on decrease
Electromagnetic flux
[Motl, 2007]
AGW.. reality or fiction?
Cycle 23
69
Cooling down? [solar cycle length, 1]
Longer solar cycle → cooler temperature
AGW.. reality or fiction?
70 Institute]
[Lassen, Danish Meteorological
Cooling down? [solar cycle length, 2]
SC22:
9y8m
SC 23: >12y4m
Will the very
long cycle yield
lower global
temperatures?
(SC24 has still not
started; Aug08 first
month since 1913
without sunspots)
AGW.. reality or fiction?
71
[www.dxlc.com/solar/]
Papers announcing coming cooling or
reduced warming [1]
Zhen-Shan, L. and S. Xian. 2007. Multi-scale analysis of global temperature
changes and trend of a drop in temperature in the next 20 years.
Meteorology and Atmospheric Physics, 95, 115–121. 2008. [cooling]
Keenlyside, N. S., M. Latif, J. Jungclaus, L. Kornblueh, and E. Roeckner:
Advancing Decadal-Scale Climate Prediction in the North Atlantic Sector.
Nature, 453, 84-88. 2008. [reduced warming]
Landscheidt, Th: New Little Ice Age instead of Global Warming?
Schröter Institute 2004. [cooling]
V. S. Bashkirtsev and G. P. Mashnich: Will We Face Global Warming in
the Nearest Future? Institute of Solar–Terrestrial Physics, Siberian Division,
Russian Academy of sciences. August 28, 2002 [cooling]
Pyilai Ch, : Predicting Solar Cycles with a Dynamo Model.
Indian Institute of Science, Bangalore. 2007. [weak cycle 24]
AGW.. reality or fiction?
72
Papers announcing coming cooling or
reduced warming [2]
AGW.. reality or fiction?
73
[Dilley, 2008]
Conclusions
• The past century warmed by ~0.7°C. The contribution of
AGW to this warming is probably much smaller than that
given by the IPCC consensus.
• The influence of GHG’s, especially CO2, is overstated,
the natural variability (of the sun) is understated.
• Climate models are still unreliable and should not be
trusted as a political decision aid.
• Climate and energy are separate problems: climate
change scares should not be used to push a particular
energy agenda!
• Future research and funding should be focused on
energy problems; useless and costly global treaties like
Kyoto should be avoided.
AGW.. reality or fiction?
74
Anthropogenic Global Warming
Reality or Fiction?
Fiction: most of the recent warming is anthropogenic
Reality: most of the recent warming is natural
Thank you for your attention!
AGW.. reality or fiction?
75