Memorandum submitted by Dr D R Keiller
(CRU 23)
BACKGROUND INFORMATION
AND INTRODUCTION
By way of introduction, my name is Dr Don Keiller,
I studied Natural Sciences at Cambridge University, graduating
with a 2.1 in 1977. After graduation I continued my studies at
Cambridge University and was awarded a PhD in 1981. Since then
I have held a variety of teaching and research positions at, Leicester,
Sheffield, and Staffordshire Universities and for the last 18
years worked in the Department of Life Sciences at Anglia Ruskin
University, where I am Deputy Head of Department. I have published
20 peer-reviewed publications, the most recent four been about
the effects of enhanced ultraviolet radiation on plant growth
and development. Since concerns were first raised about the environmental
effects of the "Ozone Hole", I have taken an active
interest in the science of Climate Change and was one of the individuals
who used the F.O.I. Act to request data from CRU.
SUMMARY OF
MAIN POINTS
National Oceanic and Atmospheric Administration
(NOAA)'s National Climatic Data Center (NCDC), NASA's Goddard
Institute for Space Studies (GISS) and CRU databases are not independent
as they all rely on the same basic ground-station data.
Instrumental temperature data for the pre-satellite era (1850-1980)
have been so widely, systematically and unidirectionally altered
that it cannot be credibly asserted what level of "global
warming" has occurred in the 20th century.
All terrestrial surface-temperature databases
exhibit very serious problems that render them unfit for determining
accurate long-term temperature trends.
All of the problems have skewed the data
to overstate observed warming both regionally and globally.
Global terrestrial temperature data are
compromised because more than three-quarters of the 6,000 stations
that once existed are no longer reporting.
There has been a bias towards removing
higher-altitude, higher-latitude and rural stations, leading to
a further overstatement of warming.
Contamination by urbanization, changes
in land use, improper siting, and inadequately-calibrated instrument
upgrades, further overstates warming.
Numerous peer-reviewed papers in recent
years have shown the overstatement of observed longer term warming
is between 30-50% from urban heat-island contamination alone.
Inappropriate selection of observing
sites, combined with interpolation to adjacent stations and vacant
data grids, may make heat-island bias greater than 50% of 20th-century
warming.
Satellite temperature monitoring has
provided an alternative to terrestrial stations in compiling the
global lower-troposphere temperature record. Their findings are
increasingly diverging from the ground station-based temperature
records in a manner consistent with evidence of a warm bias in
the surface temperature record.
Global terrestrial climate databases
are seriously flawed and can no longer be used to assess climate
trends, or validate climate model forecasts.
DETAILED SUBMISSION
1. It is my understanding that The Science
and Technology Committee will be undertaking an inquiry into the
unauthorised publication of data, emails and documents relating
to the work of the Climatic Research Unit (CRU) at the University
of East Anglia (UEA). The Committee has agreed to examine and
invite written submissions on three questions:
What are the implications of the disclosures
for the integrity of scientific research?
Are the terms of reference and scope
of the Independent Review announced on 3 December 2009 by UEA
adequate?
How independent are the other two international
data sets?
As these questions will require considerable
in-depth study to address correctly, I am unconvinced that any
single 3,000 word submission will prove adequate. Accordingly
I refer the readers of this submission to selected papers from
the peer-reviewed literature and webpages, where additional backgound
information and confirmatory detail can be obtained. There are
also a number of figures (Appendix 1, page 7) which help illustrate
points made in the text, however the text itself is freestanding.
2. With regards to the implications of the
CRU disclosures for the integrity of scientific research, a detailed
timeline and (subjective) commentary of the emails can be found
here; http://scienceandpublicpolicy.org/reprint/climategate_analysis.html.
What is absolutely clear from these emails is the Professor Jones
and colleagues at CRU conspired to obstruct reasonable and legitimate
requests for access to scientific data. This charge has been upheld
by The Information Commissioner. What these emails reveal is a
detailed and systematic conspiracy to prevent other scientists
gaining access to CRU datasets. Such obstruction strikes at the
very heart of the scientific method, that is the scrutiny and
verification of data and results by one's peers. Until all data,
adjustment procedures and computer code relating to CRU's temperature
records are released to the scientific community, for proper scrutiny
and verification, all peer-reviewed publications whose conclusions
rely on CRU's temperature records must be withdrawn as "unproven".
Similarly all policy decisions based on this data and conclusions
drawn from it are also unsafe, until proven otherwise.
3. Secondly there is the issue of the independence,
scientific credibility and integrity of CRU's and other official
temperature records. Multiple lines of evidence suggest that the
various official temperature records are neither independent,
nor credible. Here I draw the reader's attention to the report
"Surface Temperature Records: Policy Driven Deception?"
by Joseph D'Aleo and Anthony Watts, (2010). Full details are at;
http://scienceandpublicpolicy.org/originals/policy_driven_deception.html
Main submission follows:
4. DIVERGENCE
BETWEEN SATELLITE
AND GROUND-BASED
TEMPERATURE RECORDS
Five organizations publish Global temperature
data. TwoRemote Sensing Systems (RSS) and the University
of Alabama at Huntsville (UAH)are satellite measured datasets.
The three terrestrial institutionsNational Oceanic and
Atmospheric Administration (NOAA)'s National Climatic Data Center
(NCDC), NASA's Goddard Institute for Space Studies (GISS), and
the University of East Anglia's Climatic Research Unit (CRU)all
depend on data supplied by ground stations via NOAA. Hence
the three international terrestrial data sets are not independent.
When the satellites were first launched, their temperature readings
were in good agreement with the surface station data. However
over the 30 years of measurement, there has been increasing divergence
of satellite data from ground-based stations, which now, on average,
measure some 0.2°C warmer than the satellites (Figure 1,
Appendix 1). Such a difference amounts to 0.6°C per century,
a figure comparable in magnitude with the total measured warming
over the past 100 years. Moreover this divergence does not arise
from satellite errors. (Klotzbach, P J, R A Pielke Sr, R A Pielke
Jr, J R Christy, and R T McNider, 2009: An alternative explanation
for differential temperature trends at the surface and in the
lower troposphere. J Geophys Res, 114), rather a multitude
of technical issues with the ground-based stations, described
below.
5. VANISHING
STATIONS
Perhaps one of the biggest issues with the global
data is the disappearance of temperature monitoring stations from
the Global networks after 1990. Whilst more than 6000 stations
were active in the mid-1970s, only 1,500, or less, are in use
today.
Of greater concern is the observation that the
stations that were dropped from the monitoring network were mainly
rural and/or at higher latitudes and altitudes. This positioning
tended to make them "cooler" stations, hence their removal
introduced a warming bias, thus making any accurate assessment
of overall warming impossible. This is demonstrated in Figure
2 which shows that the temperature average of all global stations
does not fluctuate significantly until 1990, after which the average
temperature jumps up at precisely the time as large-scale station
drop-out. A study by Willmott et al (Willmott, Robeson
and Feddema, 1991 "Influence of Spatially Variable Instrument
Networks on Climatic Averages, Geophysical Research Letters
vol 18, No 12, pp 2249-2251) calculated a +0.2°C bias
in the global average owing to pre-1990 station closures.
6. DATA ADJUSTMENTS
The leaking of emails from CRU has initiated
examinations of the global datasets not only at CRU, NASA, and
NOAA, but in various countries throughout the World. Though the
Hadley Centre implied their data was in agreement with other datasets
and was thus trustworthy, the truth is that until all data is
released for verification, this can not be determined. That the
datasets are in agreement is not surprising given that they are
not trully independent (paragraph 4). Furthermore it is clear
that adjustment and manipulation of raw station temperature data
is the norm, rather than the exception. Temperature adjustments
are often made that are hard to explain but, with one exception
(paragraph 7), invariably increase the apparent warming. Typically
a warming trend is artificially introduced to rural stations by
adjusting earlier periods to make them appear cooler. Unfortunately
without full access to the primary temperature data and all adjustment
procedures, the accuracy of these these adjustments is impossible
to quantify. An example of such a station dataset adjustment is
shown in Figure 3. According to NOAA, adjustments are made for
the following reasons:
Time of Observation (TOBS): The
temperature data are adjusted for the time-of-observation bias
(Karl, T R, C N Williams, Jr, P J Young and W M Wendland, 1986:
A model to estimate the time of observation bias associated with
monthly mean maximum, minimum, and mean temperature for the United
States, J Climate Appl Meteor, 25, 145-160.), which occurs
when observing times are changed from midnight to some time earlier
in the day. The ending time of the 24-h climatological day varies
from station to station and/or over a period of years at a given
station. The time of observation (TOB) can introduce a non-climatic
bias into the monthly means.
Equipment Change: Temperature
data at stations that have the Maximum/Minimum Temperature System
(MMTS) are adjusted for the bias introduced when the liquid-in-glass
thermometers were replaced with the MMTS (Quayle, R G, D R Easterling,
T R Karl and P Y Hughes, 1991: Effects of recent thermometer changes
in the cooperative station network, Bull Am Meteorol Soc,
72, 1718-1724.). The MMTS adjustment program is supposed to debias
the data obtained from stations with MMTS sensors.
Station History Adjustment (SHAP):
Here the homogeneity adjustment scheme described in Karl et
al (Karl, T R and C W Williams, Jr, 1987: An approach to adjusting
climatological time series for discontinuous inhomogeneities,
J Climate Appl Meteor, 26, 1744-1763) is performed using
the station history metadata file to account for time series discontinuities
due to random station moves and other station changes. The debiased
data from the MMTS adjustment are then entered into the Station
History Adjustment Program or SHAP.
Fill Missing Data (FILNET): Estimates
for missing data are provided using a procedure similar to that
used in SHAP. This adjustment uses the debiased data from the
SHAP and fills in missing original data when needed (ie calculates
estimated data) based on a "network" of the best correlated
nearby stations. Unfortunately this algorithm can produce unusual
adjustments. Witness the effect of adjustments (Figure 4) made
at a high quality (Climate Reference Network, CRN=1 http://www1.ncdc.noaa.gov/pub/data/uscrn/documentation/program/X030FullDocument
D0.pdf) ground station (see paragraph. 8).
Urban Warming Adjustment (see
paragraph. 7): The final adjustment is for a positive urban warming
bias which uses the regression approach outlined in Karl et
al (Karl, T R, H F Diaz, and G Kukla, 1988: Urbanization:
its detection and effect in the United States climate record,
J Climate, 1, 1099-1123.). The result of this adjustment
provides the "final" version of the data.
Interestingly, Tom Karl, author of many of these
adjustment procedures, is involved with Professor Jones in many
of the CRU email exchanges. The cumulative effect of all these
adjustments is approximately a one-half degree Fahrenheit warming
(0.28°C) in the annual time series over a 50-year period
from the 1940's until the last decade of the century. This is
of a similar order of magnitude to the total amount of warming
observed (Figure 5). Whether all these adjustments work as they
should remains debatable. One, correction for Urban Warming Adjustment,
does not, as described below.
7. URBAN HEAT
ISLAND (UHI) EFFECT
Weather data from cities as collected by meteorological
stations are indisputably contaminated by UHI bias and land-use
changes. This contamination has to be removed or adjusted for
in order to accurately identify true background climatic changes
or trends. In cities, vertical walls, steel and concrete absorb
the sun's heat and are slow to cool at night. Oke (Oke, T R 1973.
City size and the urban heat island. Atmospheric Environment
7: 769-779.) found that the urban heat-island (in °C)
increases according to the formula
Urban heat-island warming = 0.317 ln P, where P =
population
Thus a village with a population of 10 has a warm
bias of 0.73°C. A village with 100 has a warm bias of 1.46°C
and a town with a population of 1000 people has a warm bias of
2.2°C. A large city with a million people has a warm bias
of 4.4°C.
This effect has been well-documented by other
studies eg Goodridge (1996), Figure 6.
However the IPCC continues to rely on a single
paper by Professor Jones (CRU) (Jones P D, Groisman P Ya, Coughlan
M, Plummer N, Wangl W C, Karl T R (1990) Assessment of urbanization
effects in time series of surface air temperatures over land.
Nature 347:169-172) that concludes that UHI only contributes
0.05°C over the period 1900 to 1990 and this is the UHI correction
that is applied to the various terrestrial temperature datasets.
However more recent work (Hinkel, K M, Nelson, F E, Klene, A E
and Bell, J H 2003. The urban heat island in winter at Barrow,
Alaska. International Journal of Climatology 23: 1889-1905)
shows an average 2.2°C UHI in Barrow, Alaska which has a
population of 4,600. Remarkably a more recent paper by Jones (Jones,
Lister, and Li, 2008. Urbanization effects in large-scale temperature
records, with an emphasis on China, J Geophys Res, 113,)
finds that UHI-related warming over China is about 0.1°C
degree per decade, or 1°C degree per century, some 20 times
greater than he previously acknowledged. Finally GISS sites are
defined to be "rural" if the town has a population under
10,000, however, as stated above, such a classification is likely
to produce a significant non-climatic warming bias in ground-station
data. Furthermore, the GISS population database is out of date
and stations at cities with populations greatly exceeding 10,000
are incorrectly classified as rural. For example, in Peru there
are 13 stations classified as rural. Of these, one station is
located at a city with a population of 400,000. Five are at cities
with populations from 50,000-135,000. Clearly current corrections
for UHI in the terrestrial temperature databases need urgent review.
8. INSTRUMENT
SITING
According to the The World Meteorological Organization's
(WMO) own criteria, which is followed by the NOAA's National Weather
Service (NWS), temperature sensors should be located on an instrument
tower at 1.5 metres (five feet) above the surface of the ground.
The tower should be on flat, horizontal ground surrounded by a
clear surface, over grass, or low vegetation, kept less than four
inches high. The tower should be at least 100 meters (110 yards)
from tall trees, artificial heating, or reflecting surfaces, such
as buildings, concrete surfaces, and parking lots. Pielke et
al (Pielke Sr, R A, C Davey, D Niyogi, S Fall, J Steinweg-Woods,
K Hubbard, X Lin, M Cai, Y-K Lim, H Li, J Nielsen-Gammon, K Gallo,
R Hale, R Mahmood, S Foster, R T McNider and P Blanken, 2007.
Unresolved issues with the assessment of multi-decadal global
land surface temperature trends J Geophys Res, 112) found
that the majority of U.S. stations surveyed did not meet WMO requirements
for proper siting. The average warm bias for these inappropriately-sited
stations exceeded 1°C, using the NWS's own criteria. A separate,
independent survey of climate stations carried out by the meteorologist,
Anthony Watts, came to a similar conclusion (Figure 7). There
is no reason to believe that stations outside of the U.S. are
any better; in fact there is evidence (paragraph 7) that they
may be worse in terms of siting and maintainance. Again current
methods of correction for poorly-sited stations are inadequate.
9. INSTRUMENT
CHANGES
The modernization of weather stations in the
United States and around the World, replaced many human observers
with instruments (HO-83 Hygro-thermometer) that initially had
major errors and "warm biases". Work by Gall (Gall,
R, Young, K, Schotland, R, Schmitz, J: 1992. The Recent Maximum
temperature Anomalies In Tucson. Are they real or an Instrument
Problem? J of Climate, 5, 657-664) identified that the
new HO-83 thermometer had a significant warm bias, whilst Karl
(Karl, T R, 1995: Critical issues for long-term climate monitoring.
Climate Change, 31, 185.) reported a sudden jump in temperature
of about 0.5°C at stations when the new thermometer was introduced.
This discontinuity (Figure 8), caused by the introduction of the
HO-83, was not adjusted for in the USHCN database for the period
from the 1980s to the late 1990s, after which the instruments
were again replaced.
10. HOMOGENISATION
It has been stated (Menne, Matthew J., Claude
N. Williams, Jr. and Russell S. Vose, 2009: The United States
Historical Climatology Network Monthly Temperature DataVersion
2. Bulletin of the American Meteorological Society, in
press) that "station siting errors do not matter". However
their method of analysis is flawed because when they compare,
for example, urban and rural stations, they do so using "post-homogenisation"
data. What this homogenisation process does is to weigh the data
from one station against that of its nearest neighbours. Whilst
this is, ostensibly, to fill in data gaps and eliminate discontinuities,
the effect is to average out individual station data. What may
have well started out as a CRN=1 station (Figure 7) is subsumed
by data from poorer quality stations (see Figures 9 and 10 for
explanation). One effect is to introduce an artificial warming
to rural station data from adjacent urban sites, hence any post-
homogenisation comparison of station data quality is meaningless.
11. SUMMARY OF
CONCLUSIONS
National Oceanic and Atmospheric Administration
(NOAA)'s National Climatic Data Center (NCDC), NASA's Goddard
Institute for Space Studies (GISS) and CRU databases are not independent
as they all rely on the same basic ground-station data.
Instrumental temperature data for the
pre-satellite era (1850-1980) have been so widely, systematically,
and unidirectionally altered that it cannot be credibly asserted
what level of "global warming" has occurred in the 20th.
Century.
All terrestrial surface-temperature databases
exhibit very serious problems that render them unfit for determining
accurate long-term temperature trends.
All of the problems have skewed the data
to overstate observed warming both regionally and globally.
Global terrestrial temperature data are
compromised because more than three-quarters of the 6,000 stations
that once existed are no longer reporting.
There has been a bias towards removing
higher-altitude, higher-latitude, and rural stations, leading
to a further overstatement of warming.
Contamination by urbanization, changes
in land use, improper siting, and inadequately-calibrated instrument
upgrades further overstates warming.
Numerous peer-reviewed papers have shown
the overstatement of observed longer term warming is 30-50% from
UHI contamination alone.
Inappropriate selection of observing
sites, combined with interpolation to adjacent stations and vacant
data grids, may make heat-island bias greater than 50% of 20th-century
warming.
Satellite temperature monitoring has
provided an alternative to terrestrial stations in compiling the
global lower-troposphere temperature record. Their findings are
increasingly diverging from the ground station-based constructions
in a manner consistent with evidence of a warm bias in the surface
temperature record.
Global terrestrial climate databases
are seriously flawed and can no longer be used to assess climate
trends or validate climate model forecasts.
February 2010
APPENDIX (1)
FIGURES TO SUPPORT THE TEXT
Figure 1

Note the increasingly divergent warm bias of ground-station
measurements
Figure 2

Note the step change in average temperatures that
occurs as station numbers fall.
Figure 3
TWO VERSIONS OF A DATASET USHCN v1 (PRIOR
TO ADJUSTMENT) AND USHCN v2 (POST ADJUSTMENT)

Note the marked cooling of past temperatures after
adjustment.
Figure 4

Again note the "cooling" of past temperature
data.
Figure 5

Note the overall warming effect of these adjustments.
Figure 6

(Goodridge, J.D. (1996) Comments on "Regional
Simulations of Greenhouse Warming including Natural Variability".
Bull Amer Meteorological Society 77:1588-1599). Note increased
warming in more densely populated areas.
Figure 7

Figure 8

Note the uncorrected discontinuity at the time of
instrument change.
Figure 9

Figure 10

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