Solar Driven Warming From 1980 To 2000
oobnz
Scafetta-Wilson Paper: Increasing TSI between 1980 and 2000 could have
contributed significantly to global warming during the last three decades
13 Mar 2009
QUOTE: . Both 'mixed' composites demonstrate a significant TSI increase of
0.033%/decade between the solar activity minima of 1986 and 1996, comparable
to the 0.037% found in the ACRIM composite.
Some previous TSI reconstructions
Via Roger Pielke Sr. climatescience blog:
A New Paper On Solar Climate Forcing "ACRIM-Gap And TSI Trend Issue Resolved
Using A Surface Magnetic Flux TSI Proxy Model By Scafetta Et Al 2009
At the December 2008 NRC meeting "Detection and Attribution of Solar Forcing
on Climate" there was extensive criticism by Gavin Schmidt and others on
the research of Nicola Scafetta with respect to solar climate forcings. He
was not, however, invited to that December meeting.
There is now a new paper that he has published that needs to be refuted or
supported by other peer reviewed literature (rather than comments in a
closed NRC meeting in which the presentors would not share their powerpoint
talks).
The new paper is
Scafetta N., R. C. Willson (2009), ACRIM-gap and TSI trend issue resolved
using a surface magnetic flux TSI proxy model, Geophys. Res. Lett., 36,
L05701, doi:10.1029/2008GL036307.
The abstract reads
"The ACRIM-gap (1989.5-1991.75) continuity dilemma for satellite TSI
observations is resolved by bridging the satellite TSI monitoring gap
between ACRIM1 and ACRIM2 results with TSI derived from Krivova et al.'s
(2007) proxy model based on variations of the surface distribution of solar
magnetic flux. 'Mixed' versions of ACRIM and PMOD TSI composites are
constructed with their composites' original values except for the ACRIM gap,
where Krivova modeled TSI is used to connect ACRIM1 and ACRIM2 results. Both
'mixed' composites demonstrate a significant TSI increase of 0.033%/decade
between the solar activity minima of 1986 and 1996, comparable to the 0.037%
found in the ACRIM composite. The finding supports the contention of Willson
(1997) that the ERBS/ERBE results are flawed by uncorrected degradation
during the ACRIM gap and refutes the Nimbus7/ERB ACRIM gap adjustment
Fröhlich and Lean (1998) employed in constructing the PMOD."
A key statement in the conclusion reads
"This finding has evident repercussions for climate change and solar
physics. Increasing TSI between 1980 and 2000 could have contributed
significantly to global warming during the last three decades [Scafetta and
West, 2007, 2008].
Current climate models [IPCC, 2007] have assumed that the TSI did not vary
significantly during the last 30 years and have therefore underestimated the
solar contribution and overestimated the anthropogenic contribution to
global warming."
Interestingly, TSI has been on a slight downtrend in the past few years as
we get closer to solar minimum.
The graph below is from the ACRIM project page.
It remains to be seen if we have hit the minimum yet.
Warmest Regards
Bonzo
oobnz
<erschro...@gmail.com> wrote in message
news:32600594-b169-4f8a...@e38g2000yqa.googlegroups.com...
>
> Warmest Regards
>
> Bonzo
From the paper:
"We estimate that the
ACRIM upward trend might have minimally contributed
10–30% of the global surface temperature warming over
the period 1980–2002."
Nothing new --- that value has been floating around for some time.
Still leaves the majority of the warming from greenhouse gases.
*****************************************************************
CORRECTION
Still leaves the majority of the warming from El Nino driven by solar
activity.
Warmest Regards
Bonzo
qqq
Bonzo is an incompetent merchant of filth whose theories are debunked here:
http://www.cru.uea.ac.uk/cru/info/warming/
Where it says:
The time series shows the combined global land and marine surface
temperature record from 1850 to 2008. The year 2008 was tenth warmest on
record, exceeded by 1998, 2005, 2003, 2002, 2004, 2006, 2001, 2007 and
1997. This time series is being compiled jointly by the Climatic
Research Unit and the UK Met. Office Hadley Centre. The record is being
continually up-dated and improved (see Brohan et al., 2006). This paper
includes a new and more thorough assessment of errors, recognizing that
these differ on annual and decadal timescales. Increased concentrations
of greenhouse gases in the atmosphere due to human activities are most
likely the underlying cause of warming in the 20th century.
The key reference for this time series is:
# Brohan, P., J.J. Kennedy, I. Harris, S.F.B. Tett and P.D. Jones,
2006: Uncertainty estimates in regional and global observed temperature
changes: a new dataset from 1850. J. Geophysical Research 111, D12106,
doi:10.1029/2005JD006548
The 1990s were the warmest complete decade in the series. The warmest
year of the entire series has been 1998, with a temperature of 0.546°C
above the 1961-90 mean. Thirteen of the fourteen warmest years in the
series have now occurred in the past fourteen years (1995-2008). The
only year in the last fourteen not among the warmest fourteen is 1996
(replaced in the warm list by 1990). The period 2001-2008 (0.43°C above
1961-90 mean) is 0.19°C warmer than the 1991-2000 decade (0.24°C above
1961-90 mean).
Analyses of over 400 proxy climate series (from trees, corals, ice cores
and historical records) show that the 1990s is the warmest decade of the
millennium and the 20th century the warmest century. The warmest year of
the millennium was likely 1998, and the coldest was probably (but with
much greater uncertainty) 1601.
The Inter-governmental Panel on Climate Change in its most recent report
in 2007 stated:
'Warming of the climate system is unequivocal, as is now evident
from observations of increases in global average air and ocean
temperatures, widespread melting of snow and ice, and rising global
average sea level.'
'Most of the observed increase in globally averaged temperatures
since the mid-20th century is very likely due to the observed increase
in anthropogenic greenhouse gas concentrations12. This is an advance
since the TAR's conclusion that "most of the observed warming over the
last 50 years is likely to have been due to the increase in greenhouse
gas concentrations". Discernible human influences now extend to other
aspects of climate, including ocean warming, continental-average
temperatures, temperature extremes and wind patterns'
Q
--
The only thing to fear is invisible stupidity.
oobnz
"qqq" <q@q.q> wrote in message
news:49bf1b8d$0$189$e4fe...@news.xs4all.nl...
> oobnz wrote:
> The time series shows the combined global land and marine surface
> temperature record from 1850 to 2008. The year 2008 was tenth warmest on
> record, exceeded by 1998, 2005, 2003, 2002, 2004, 2006, 2001, 2007 and
> 1997.
IOW 2008 is the coldest year this century!
This time series is being compiled jointly by the Climatic
> Research Unit and the UK Met. Office Hadley Centre. The record is being
> continually up-dated and improved (see Brohan et al., 2006). This paper
> includes a new and more thorough assessment of errors, recognizing that
> these differ on annual and decadal timescales. Increased concentrations
> of greenhouse gases in the atmosphere due to human activities are most
> likely the underlying cause of warming in the 20th century.
>
> The key reference for this time series is:
>
> # Brohan, P., J.J. Kennedy, I. Harris, S.F.B. Tett and P.D. Jones,
> 2006: Uncertainty estimates in regional and global observed temperature
> changes: a new dataset from 1850. J. Geophysical Research 111, D12106,
> doi:10.1029/2005JD006548
>
> The 1990s were the warmest complete decade in the series. The warmest
> year of the entire series has been 1998, with a temperature of 0.546°C
> above the 1961-90 mean.
Now why would an AGW whacko pick 1961-90 as the reference?
Anyone ...?
Because this was a period of global cooling and using this as a reference
makes the El Nino warming from 1980 to 1998 appear that much greater!
Did I hear "hidden agenda"??
2008 was tenth warmest on record, exceeded by 1998, 2005, 2003, 2002, 2004,
2006, 2001, 2007 and 1997.
2008 was cooler than 1997
2008 was cooler than 1998
2008 was cooler than 2001
2008 was cooler than 2002
2008 was cooler than 2003
2008 was cooler than 2004
2008 was cooler than 2005
2008 was cooler than 2006
2008 was cooler than 2007
http://www.cru.uea.ac.uk/cru/info/warming/
Warmest Regards
Bonzo