Is the reported global surface warming of 1978 to 1997 real?

Conference on Global and Regional Climate Variability

Santa Fe, NM Oct 31-Nov 4, 2011

(Prof.) S. Fred SingerUniversity of Virginia/ SEPP

<singer@sepp.org>

Three Fundamental Issues: in Climate science, Economics, Policy• 1. Is climate change of the 20th century

human-caused (anthropogenic GW -- AGW)?• 2. If AGW is significant, is a future warmer

climate (and higher CO2 level) good or bad ?• 3. If a future warming is calamitous, can we

really do something about it – technically and economically? Can we lower atmospheric CO2 levels: phase out fossil fuels, capture & sequester CO2, make solar and wind power reliable and cheap, produce low-cost biofuels?

IPCC reports cannot show evidence in support of AGW

• IPCC-1 [1990] claimed CO2- temp correlation. But no warming seen 1940-75 or since 2002

• IPCC-2 [1996] claimed model-obs ‘fingerprints’ agreed. But claim based on doctored graphs.

• IPCC-3 [2001] claimed (failed) ‘Hockeystick’ as proof. But 20th cy warming was not unusual.

• IPCC-4 [2007] claimed post-1978 warming as proof of AGW. *But such warming is not real

Sfc Warmings reported for 20th cy:1910-40 is real, but not 1978-2000• Sfc Warming of 1910-40 confirmed by proxies• Warming of 1978-2000, used by IPCC to claim

AGW – shown by PhysicsToday and by BEST, but not seen by independent datasets:– Atmospheric data (satellites, radiosondes)

• Disparity between GH models and Observations

– Ocean data (SST, NMAT, Heat Content-OHC)– Proxy data (tree rings, ice cores, ocean/lake

sediments, stalagmites, etc) __________________________

Why the Disparity: Land-Sfc temp vs All other data

a.

b.

BEST (Berkeley Earth Sfc Temp): • Uses (surface) temp data from weather-

station thermometers, like CRU, GISS, NCDC • Hence finds similar global sfc trends, but is

fully documented and transparent• BEST used only land-based data – so far• One-third of BEST stations show cooling • 70% of US stations are poorly sited • Did station “demographics” change between

1970-2000? UHI? Airports? Other problems? • Has not performed geographic decomposition

Reported sfc warmings: 1910-40 is real; 1978-2000 is not. Evidence:

• MSU-Satellites show no atmospheric warming• Balloon-radiosondes: little atm. warming trend• Missing amplification “puzzle” [Santer 2005]• Solar activity “paradox” [Lockwood 2007]• NRC-NAS [2000] cannot reconcile sfc-atm temp• SST trend – an artifact of instrumentation?• OHC: data show no appreciable warming• Proxy data show no warming. Hockeystick hides

“divergence” post-1978: “Mike’s Nature trick”?

Earlier indications of disparity between sfc and troposphere temp

• [from HTCS 1997]: In tropics, sfc data show pos trend while satellite temp show neg trend

• Suspected causes: Urban Heat Island effect; land use changes; changes in sampling population (latitude, altitude, fraction of airports) between 1970 and 2000

Disparity between tropical sfc and atm trends, as already indicated by data in 1997

A more detailed view of the disparity of trends (K/dec):

Douglass, Knox, Pearson, Singer IJC 2007

Four “puzzles” –easily solved

• Disparity between GH models and sfc temperatures (1970-2000): IPCC-4 Fig.9.5-b

• Santer [Science 2005]: Lack of “amplification” for decadal trends, but not short-term ones

• NAS-NRC [2000] failed to “reconcile” sfc with tropospheric trends (balloons and satellites)

• Lockwood & Frohlich [2007] claim disparity between solar data and a sfc warming trend

IPCC-AR4 Conclusion on AGW:Just a “curve-fitting” exercise?

• “Most of the observed increase in global average [surface] temperatures since the mid-20th century is very likely [90 to 99% certain] due to the observed increase in greenhouse gas concentrations.” [Ref: IPCC-AR4 [2007], Summary for Policymakers, page 10]--------------------------------------------------

• IPCC-AR4 Fig 9.5b (p.684) assigns the difference between “naturally-caused” (blue) and “observed” (black line) warming to GHG. [Hence, in the absence of such a difference (i.e., absence of post-1978 warming), the human contribution would be ~zero]

Amplification (Scaling Ratio) of Surface Warming TrendFig. 3. Atmospheric profiles of temp scaling ratios in models, theory, and radiosonde data.

B D Santer et al. Science 2005;309:1551-1556

NAS-NRC Report [2000]:“Reconciling Observations of Global Temperature Change”

• The NAS-NRC panel (chaired by Prof J M Wallace) failed to “reconcile” the disparity in temperature trends between SURFACE and TROPOSPHERE --as measured by balloon-borne radiosondes and also by independent Satellite Microwave Sounding Units (MSU).

• The simplest explanation would be to discard the reported sfc warming trends. Yet the panel preferred the opposite conclusion, disregarding also the “moist adiabatic” adjustment to the lapse rate.

Solar “Paradox” of Lockwood-Fröhlich

• “There is considerable evidence for solar influence on the Earth's pre-industrial climate and the Sun may well have been a factor in post-industrial climate change in the first half of the last century. Here we show that over the past 20 years, all the trends in the Sun that could have had an influence on the Earth's climate have been in the opposite direction to that required to explain the observed rise in global mean temperatures.” [emphasis added] [Ref: ProcRoySoc 2007]

• Comment: The absence of this reported post-1978 surface warming explains the (artificial) paradox

Be-10 – proxy for Cosmic Rays and Solar Activity

Ocean data show no significant warming during 1978-1997

• Troposphere temp same over land and ocean• NMAT results disagree with SST trends• SST results: an artifact of increasing buoy data• Problem: Where does downwelling IR energy go after

absorption in sea surface “skin”?• Proxy data (corals) show no warming• Ocean Heat Content (OHC) shows no increase– Problem: Inconsistencies in downward energy transfer from

“Mixed layer” to deep ocean

(Ocean-minus-Land) Atm Temp Difference: from MSU-Tropics-LT

UK Met Office Historic Marine Air Temperature--MOHMAT/HadMAT

Night-time Marine Air Temp (NMAT) is warming less rapidly than average SST during 1978-1997

• NMAT 1990 temp is about equal to its 1940 value • Indicates a large diurnal range of SST, with day-time

warming trend due to increasing drifter buoy data• Thus reported SST warming trend may be an artifact

of instrumentation; not a GH effect• Christy, JR, et al. 2001. Differential trends in tropical SST and atmospheric

temp [NMAT] since 1979. GRL 28(1), 183–186, doi:10.1029/2000GL011167.• Trends and Variations in South Pacific Island and Ocean Surface

Temperature, Folland CK, et al. 2003 J. Climate 16(17), 2859-2874.• Global analyses of SST, sea ice, and NMAT, Rayner NA, et al. JGR 108,

doi:10.1029/2002JD002670, 2003

5 year running average. Source: John Kennedy

Buoys introduce an Artificial Trend

• The claimed SST warming may be close to zero and an artifact of the measurements that combine ship and buoy data. We base this assertion on satellite and independent radiosonde data, on NMAT data, as well as on ocean heat content (OHC) data. Observations of late 20th century Sea Level Rise (SLR) and of solar activity changes do not support any significant global SST warming -- nor do proxy data (corals).

Temperature Data from Buoys Rose from Zero (1980) to 90% (2010),

creating an artificial warming trend

• The contribution from drifter buoys rose almost linearly from 0% in 1980 to 72% in 2010. During the same interval, moored buoys rose from 0% to 18%

• Ref: Composition of ICOADSv2.5.1 Annual number of sea surface temperature observations per year by platform type, expressed as a fraction of total number of observations. [Figure 2 of Effects of instrumentation changes on sea surface temperature measured in situ

• Elizabeth C. Kent, et al. online: 17 MAY 2010. DOI: 10.1002/wcc.55. • in Wiley Interdisciplinary Reviews: Climate Change• Volume 1, Issue 5, pages 718–728, September/October 2010

Composition of ICOADSv2.5. (a) Annual number of sea surface temperature observations per year by platform type. (b) As (a) but expressed as a fraction of total number of observations. [For the period centered on around 1900, most of the ‘unknown or other’ observations are of unknown source, and after 1962 almost all have come from oceanographic sources.]Source: Kent, Elizabeth et al. 2010. “Effects of instrumentation changes on sea surface temperature measured in situ”. Wiley Interdisciplinary Reviews: Climate Change. Vol 1(5) Sept/Oct 2010

T + dT

SUN

BUOY

IR

Engine Inlet

SHIP

Ocean Heat Content

Proxy data of temperatures provide independent confirmation

• Tree ring data (shown in HTCS 1997) confirm 1910-40 warming but not a 1978-1997 wmg

• Ice core data (Dahl-Jensen et al. Science 1998)– “Temperature cools between 1940 and 1995.”

• Assorted proxies (Ljungqvist 2011)• Awaiting release of suppressed post-1978

Hockeystick’s multi-proxy temperature data

Fig. 16. The climate record as deduced from the width of tree rings. Compared are the ring-width chronology (solid line) and the reconstruction of Arctic annual temperature anomalies (dashed line) [Jacoby et al. 1996, reprinted with permission, (c) American Association for the Advancement of Science]. Note the sharp increase between 1880 and 1940.

IPCC 1990From H. H. Lamb, first Director of CRU at EAU

IPCC 2001From M. Mann, the celebrated hockey stick!

(see posting of May 9, 2008 in http://climateaudit.org for further discussion of IPCC 1990)

Local warming can distort global trends

• Example: Urban Heat Island effect in Calif, tied to population density, affects temp levels and trends; subsequent selection of “best” stations may favor global warming trend

• Drastic changes in number of stations in 20th cy, accompanied by “demographic” changes of the samples; could produce artificial trends.

• E.g., from 1970 to 2000 airport stations increased globally from 40% to 80%

Urban Heat Island Effect

Temperature Trends at 107 Californian Stations 1909 to 1994Stratified by 1990 population of the county where station is located

(A) Large Counties: More than 1 million peopleAverage 29 stations

(B) Midsized Counties: 100,000 to 1 million peopleAverage 51 stations

(C) Small Counties: Less than 100,000 peopleAverage 27 stations

Tem

pera

ture

in d

egF

Fig. 17. Distribution of temperature trends for California weather stations. The arrows indicate the stations selected by GISS for a global temperature compilation [Christy and Goodridge 1995].

NUMBERS OF WEATHER STATIONS AND GRID BOXES

11yr weighted meanSource:ftp://ftp.ncdc.noaa.gov/pub/data/ghcn/v2

Conclusions on 1978-97 Temp

• Little global surface warming since 1940 – contra IPCC – as shown by abundant evidence

• This removes support for IPCC-claimed AGW • Reported sfc warming (1978-1997) likely due

to biased selection of weather-station data• Suppressed (post-1978) Hockeystick proxy

data may supply key evidence; we need to examine them.

Cause of GH model-Obs Disparity: Neg. Feedback or CO2 Saturation?

• CO2 Saturation – calculable from spectroscopy• Neg Feedback: Three basic possibilities to explain

model-obs disparity – with data deciding:1. Enhanced evaporation & low-level cloudiness2. “Iris Effect” (Lindzen): reduction in cirrus layer3. Reduced Upper Troposph Water Vapor (UTWV)

– Due to Enhanced Hadley Circulation and Subsidence (Ellsaesser); Due to local subsidence – between cloud tops (Wm Gray); Due to detrainment (Lindzen)

So what is causing climate change?• Internal: Atmosphere-ocean oscillations:• PDO (Pacific Decadal Oscillation); NAO (North Atlantic Oscill; Arctic Oscill; etc • External: Solar variability:

– UV variations affecting stratospheric ozone and tropospheric circulation (Haigh)– Solar-wind-interplanetary magnetic field, affecting cosmic rays and cloud albedo (Svensmark, Tinsley)

• A

Pacific Decadal Oscillator (PDO) 30 year cycles or warming and cooling

Warm Cycle Cold Cycle

Stalagmite Records in Oman Stalagmite Records in Oman

14C – a Proxy for Solar Activity18O – a Proxy for Temperature

The stalagmite record shows a remarkably close

correlation between 14C and 18O over a period of more

than 3,000 years.

Thus, a strong association exists between solar activity

and temperature.Neff et al. (2001) One Century Duration!