Download Overlooked Scientific Issues in Assessing ... Greenhouse Gas Warming. ()r{~/~A:-1 R. A. Pielke

fZ--I'i-~
()r{~/~A:-1
Overlooked Scientific Issues in Assessing Hypothesized
Greenhouse Gas Warming.
R. A. Pielke
Department of Atmospheric
Colorado 80523, USA
Science, Colorado State University, F~rt Collins,
I
ABSTRACT
This paper presents severa.1issues related to the gree~house gas globa.1 ,,'arming
hypothesis which should be satisfactorily addressed bfrore costly control requirements are imposed on society. The questions which n d to beans"'ered include
the importance of other anthropogenic influences suc as landscape changes and
enhanced atmospheric a~rosolloading,
Controls su h as conservation and improved energ)' efficiency, of course, which are benefits to society should be implemented regardless of globa.1climate change,
KEY WORDS
Gr~nhouse
\\'arming
issues, Climate
change, Global Iwarming
1. INTRODUCTION
Dllring the last several years, there has been considerable concern expressed by the media, members of the
scientific community, politicians, and others concerning a global ~.arming resulling from anlhropogeniccaused increases in certain trace gases in lhe almosphere. These trace gases, ~.hich include carbon dioxide, methane, chlorofluorocarbons,
and nilrous oxide,
reduce the amount of the earth's radiation which is
emitled lo space. Since 1880, for example, the concenlration of carbon dioxide has apparently increased very
systemalically ~'ilh only seasonal fluctuations of about
6- 7 parts per million from an estimaled annual average
value of 290 parls per million in 1880 to 3.)0 parts per
million at the current lime (see Figure la for the 1958 1984 period), ~'hile the surface air temperature record
(based almost exclusively on land data) has behaved as
sho\\.n in Figure lb. Numerical models of the global at-
mosp ere and ocean circulations (referred to as general
circul lion models -GCMs) have been used lo investigate l e impact on climate of an increase in these trace
gases. The Environmental Protection Agency (EPA)
COlIC! ded in 1983 based on these models. for example.
lhal n increase or the average global temperatures or
5°C ). the ).ear 2100 "'ith an incrcase or sea level up
to ar und 2 meters "'ill result because or the global
enha cement or these gases. The \Vorld ;\Ieteorological
rganization has concluded that greenhouse gas
cause "'arming could cause a global ".arming of 1.5°C
to 4, °C by the middle of the ncxt century.
T Ie purpose of this paper is to discuss a number of
serio s shortcomings in the GC~f model simulations
\"hid ha\'e produced these conclusions regarding climater change, These limitations, "'hich are either inadeq,atel)' hand!ed or not represented at all in GC~fs,
are s~mmarized in this paper.
*
Pa7lCTTotci"cJ 10 A7I"'1990
anJ in final fa"" 10 D.ccm6cT 1990
100
Environmental Soft,,'are, 1991,Vol, 6, No, 2
issues.
l),lper originally appeared in the Proceedings of
the ~990 ElE'Ctric Utility BusinES$En\;ron~nt
Con~rencc and E.xhibition.
Othe
scientists
ha,e also raised concern that a
greel1hou
global ,,"arming has ba-n o,'erstated because of atural and man-caused compensating effects
(e.g. Re fsnyder7 and Lindzen8). P. ~ficllaels, State
Climatol g~t of \!irginia, has been particularly out-
spoken c ncernil1g an overstatcment of a greenhouse
gas cau d warming (e.g. Michaels9), GCM investigators ar also raising cautions regarding the realism
of their .mulations. Cess et 0/.1°, for example, compared 14 GC~ts and found a large sensitivity bet\\'een
models
simulated sea surface temperature due to
different reatmenls of the cloud-climate feedbacks in
tile mode s. Guto".ski tt aV' have sbo".n that the disFigure
1:
at ,lJauna
monthly
sllrcmtnt.s.
K tflingl,
plied
(a)
Loa
avtrage.s
Conctntration
Obstrvatory,
dttennined
of
Hau'aii.
from
Based on data rcporltd
suppltmtnttd
by pErsonal
by data from
communication
atmosphtric
Dots
CQoz
indicate
continuolls
mta.
by Bacastow
rcctnt
(from
Bolin
ytars
and
sup-
tt 01.2.)
crepanci
bet\\'een GCMs in the simulation of do\\'n\'.ard Ion \\.ave radiati\"e fluxes are larger than the flux
changes
iated ,,'ith doubling carbon dioxide in the
modeled
actually
Figure 1: (b) Comparison of the annual global and
hemispheric temperature change for the Hansen and
Lebedeif' data and the Jones et al.~.5 data set (after
Hansen and Lebedeif'; from Karl et al.6.
tmospheres.
Also,
evident in Figure Ib, and reported by Thomas Karl rthe National Climatic Data Center (NOAA
Report12 .most or the global ,,"arming that has occurred 0 r tbe last century occurred btlo~ the recent
rise in gr nhouse gas concentrations. Between 1919
and 1986 according to that Report, temperatures rose
only 0.1 .C yet greenhouse gases increased by 30%.
From 19 I to 1979, the global temperatures over land
ooled.
Figure 2 Soyb,an trnnspiration efficiency as a func.
tion of ~ re[atit'e to trnnspiration efficiency at ambient C 2' The points were tltttnnined from the mea.
suremen s of Rogers et al,14, The clln'e is a [og regression fit
TE = -3,236 + o. i297 [n C~, r = 0, 94;
from Ki 9 et 0/.13),
Environtnenlal Software, 1991,Vol. 6, No.2
101
Ot.'trlocltd
Scltnl.fic
Issvtj:
R.A.
Pit/l(
2. INCREASED CARBON DIOXlDE CONSUI\WTION ~ULTING
FROM INV1GoRATED PLANT GROWTH ON LAND AND
IN TJ-IEOCEAN
Ir vegetation gr~,th is enhanced because or an enrichment in carbon dioxide, the importance or this greenhouse gas to global ,,'arming would be reduced. Figure 2, reproduced rrom King et 0/.13, documents that
soybean transpiration efficiency, and therefore soybean
yield, ,,'ould increase if CO2 concentrations are elevated, Ir the response is characteristic of natural and
other agricultural crops, a substantial portion of the
anthropogenic carbon dioxide emissions could be absorbed in biomass resulting in a benefit to mankind,
3. INABILITY FOR GCM MODELS TO
PROPERLY RE50LVE THE EVOLUTION OF
EXTRATROPICAL AND TROPICAL CY
CLONES DUE TO THEm POOR SPATIAL
RESOLUTION
The horizontal grid spacing of general circulation models is around 400 km. As shown by Pielkel$, as least
four grid increments are required to reasonably represent an atmospheric feature, thus this grid resolution
\"ould only permit features 1600 km or larger to be
reasonably represented in the models, Since extratropical cyclones often are observed to have horizontal
".avelengths as small as 500 km or so, they are poorly
represented in these models, Since these features provide the major physical mechanism for the exchange of
heat, moisture, and momenlum bet,,'een the sublropics and lhe polar regions, the inability of GCM representations to adequately represent these exchanges is a
serious shortcoming" Tropical cyclones, ".hich also provide an important mechanism for exchanges bet""een
the tropics and higher latitude is even more poorly represented since iu scales of important ph)'Sical processes
includes the eye wall ,,'hich can be tens of kilometers in
radial size. Pielke16 discusses this shortcoming further.
have
so.
n extent
lution
on the order
tenti
Up~'elling of deep, cold ocean ~'aters occurs at a number of locations around the world including the equalorial Pacific, around Anlarctica, and off the ,,'esl coast
of Norlh America, northern South America, norlh~'esl
Africa, southwest Africa, and elsewhere. Caused by the
direction and speed of the wind al the ocean surface,
these up,,'elled regions of cold surface waters usually
102
Environmental Sofl.y,'are,1991,Vol. 6, No.2
dire.:tion
GC~ls
of 400 km,
sinks for carbon
dioxide
of 50 km
have spatial
these
important,
or
rC$o.
po-
are ignored.
5. 0 CURRENCE OF GREATER GLOBAL
CLO D COVERAGE AS A RESULT OF COLLOI ALLY MORE STABLE CLOUDS DUE
TO
THROPOGE!'.T}C INPUT OF AEROSO
~
FigUr 3, reproduced from Warren et 0/.17, indicates
that loud coverage over the oceans has increased by
about 3% since 1930. \\'hile the physical explanation
for thIs increase is unknown, it could be because the anthro~genic
input of aerosols (i.e. cloud condensation
nucleil) has made the clouds colloidally more stable. so
that ~hey persist longer before precipitating.
,
FigU fe 3: Total annual
ot'(r
4.
INABILITY
FOR GCM MODELS TO
PROPERLY RESOLVE REGIONS OF OCEAN
UPWELLING WHOSE COLD WATERS CAN
El\TJIANCE THE OCEANIC UPTAKE OF
CARBON DIOXIDE
in one spatial
Si ce atm~pheric-ocean
global cloud corerage
the oceans (rcproJuced
from
microfich~
in pcrccnt
in IJ'arrcn
et aI17).
to estimate the potential impact of such a change
in clbud co\'erage on the earth's equilibrium temperature~ TEl
J
0'11 = 5(1 -A)
(1)
,,"he e 0' is the Stefan-Boltzmann
constant, 5 is the
me n solar irradiance at the earth's mean orbital p<>~" n, and A is the average albedo. Equation (1) is a
Sit
bat nce equation between the incoming radiation ener
from the sun ,,"hich is absorbed by the earth (the
OlcrlocJ;cJ Sciclltlfic
right sid~ of (I », And th~ radiation en~rgy emitted
by the earth (the left side (I». While this heat balance does not provide any information regarding the
globa! surface temperature,
it does provide a measure
of the sensitivity of the land-ocean-atmosphere system
to changes in the amount of solar radiation a\'ailable
to the planet.
By using differentia! calculus and assuming small
changes and inserting observed values for <T and S
(Pielke and A vissar18), Equation (I) can be re~'ritten
as
6TE = -268~A
(2)
where TE = 283°K wasused.
Equation (2) indicates that a change of albedo of
+3% over the oceans(which co\-er about 75% of the
earth'5 surface so thal the global average change of
albedo would be 6A = 2.25 if no cloud changes occurred over land) would resull in an equilibrium temperalure change of over -6°C! Such a sensitivity to
albedo suggeststhat t.heincreasein cloud coveragereporled on above could compensat.e
for any greenhouse
gas warming, and even result.in a global cooling!
6. MODIFICATION OF THE AMOUNT OF
SOLAR RADIATION REFLECrED BACK INTO SPACE DUE TO MAN-CAUSED LANDSCAPE CHANGrn
y
EVAPOMOD
7.
THE
AT
tICATION
ION
AND
OSPHERE
CAUSE
lsslics: RA.
Piclcc
INTRANSPIRATION
THE
A1\10UNT
AS
A
LANDSCAPE
RESULT
TO
OF
OF
?-.1AN-
CHANGES
Landscapechanges also alter the partitioning of turbulent hea fluxes into sensible and latent heat componenls and he movement of water between the earth's
surface an the atmosphere. Sensible heat fluxes directly ~'ar the atmosphere, ~'hile latent heat is represented b evaporation from surfaces and transpiration from egetation ~'ith any ~'arming not realized
until cond nsation and/or deposition to liquid and/or
iceoccurs primarily in clouds). All man-caused landscapechan es will have some impact 00 this heat and
~'aterbud et.
Irrigat d land representsone example of this effect.
Figure 4 d uments satellite measuredsurface temperaturesove an area in northeast Colorado in which this
land pract ce is applied, Temperatures are o\'er lO°C
coolerove the irrigated area at this time of the day, as
a\'eraged ver two weeks during a particular summertime peri.
Aircraft measuremen~ made o\'er this
area (Seg et 41.11)document that this area is also
much mor moist than the surrounding dryland area,
thus irrig ted areas may be associated ,,'itb changes
in cumulu cloud co\'erage and intensity (Pielke and
Zeo&11).
Changes in land surface reflection, if over a large enough
area, could similarly influence the earth's equilibrium
temperature.
If Equation (2) is rewritten as to consider only land surfaces (,,"hich cover about 25% of the
earth's surface), then
As an example of documented land surface changes,
a forest in the eastern United States has an albedo as
viewed from space on the order of 0.15 to 0,20, while if
'il \'.ere cleared and replaced by agricultural crops, the
albedo can be up to 0.30 (RosenbergI9).
~ <)1
CiN
.:,:",.:::;~.
.";*"1"~;:::O;~:"1'"~'~l:
~TE = -6i6A
Here 6A is the average change of albedo on land.
Therefore a land-average increase of 6A of 1% ".ould
result in a change in the equilibrium temperature of
-O.67°C. A decrease of 1% would correspond to a O.67°C
"'arming. Similarly, a 25% change in land surface albedo
over I % of the land surface "'ould yield the same result.
~
c::;:,
Ki:..%"J
t
J4Q
Figure 4:1
a/11ft
omposite
at 1 00 LST
of GOES
for
the
period
dcrived
surface
1 August
I
tempcr.
1986
to
15
.4ugast 1 86 for northeast Colorodo (FC. Fort Collins;
F.\l. Fo Morgan; GR -Grecley; from Segal ct 0/.20).
~
8. CLO S WInCH CONTAIN SULPHATE
PARTI ~,RESULTING
FROM FOSSIL
FUEL
MBUSTION, HAVE A ffiGHER
ALBED
THAN PRISTINE CLOUDS
Satellite ~bservations discussed in the November 1989
issueof SFientific A merican, and assuggestedby T\\'o-
Environ~ental Soft\\'are, 1991, Vol. 6, No.2
103
Orfrlockt,l
Scitnlific
155VtJ: RA
Pit/Ie
me}" tt a/.23, indicate that sulphate particles in clouds
illtroduced by fossil fuel burning could be enhancing
the brightness of these clouds from \\'hat they \\'ould
be naturally (the percent or cloud coverage could also
be higher because the additional sulphate aerosols act.
to make clouds colloidally more stable -see Section 5
above).
Vsing Equation (2), if the increase in albedo is 10%,
and the affected area represents 10% of t.he earth's surface, a decrease in TE of 2.7°C would be expected.
at II: t, temperatur('S ha\'e not ~n
increasing at r('pr('Sl:n ati\'e sites on the Antarctic conlinent despite the
conti ued increase in greenhouse gas concentrations.
Accor
from
simul
surra
ary.
Augu
in lh
ing to Schlesinger's2$ summary of the results
vera I GCMs, a doubling of carbon dioxide is
ted to cause a ,,'arming of 2°C to 6°C in the
air temperature in December, January, Febrund of even larger increases in June. July, and
t. Not even a hint of warming is seen, ho"'ever,
Antarctic data.
Si
ilarly, Michaels tt 0/,26 finds a departure of only
9. GREATFET WARMING IS PREDICTED
TO BE IN POLAR REGIONS, AND YET
WARMING HAS NOT OCCURRED
0,3°C in 1985 above the 100 year mean over most
All GCM simulations indicate that global ~'arming
should be more pronounced at polar latitudes. Figure
5, reproduced from Sansom2~1sho~'s that since 1960,
lion.
Figure 5: Time serifs plots for Faraday, Mirny,
Base, and Amundsen-Scott.
The large amplitude
shou's the actual
monthly
a trend
mfan
temperatures,
component,
Scott
line
the small
amplitude
line
and the dottt'd
line
104
Environmental Software, 1991,Vol. 6, No.2
,.
of No th America, despite the model results given in
Schl inger's summary which indicates a substantia!
"'arm ng should be occurring in that geographic loca-
1
a re
rence line
the e d points
at the 5% trimmed
of a reg~ssion
are s ou'n by "+"
signs (from
mean
line through
Samson24 ).
let'el,
the rau'
Also,
data
nificant ~ardship. ho\\Oevcr. are in this \\riler's opinion
10. SINCE THE ATMOSPHERE IS A NONLINEARLY ~PONDING
SYSTEM. EVEN
prematu~eo
\VITH ALL RELEVANT PHYSICS FAITH12. AC1<NOWLEDGEr..1ENTS
FULLY REP~ENTED. THE GCMS COULD
ONLY SIMULATE EXAMPLES OUT OF A
The uthor appreciates the discussions \\.ith Pat
SPECTRUM OF POSSffiLE ATMOSPHERIC
~fichaels
Dave Ra.ndaU, and Tom Vonder Haar regardRESPONSESTO INCREASED GREE~1JIOUSE
ing
this
t
pic. Also, Cypress ~finerals is appreciatively
GASES
The shortcomings described above regarding GC~fs,
ho\\.ever, does not suggest that we forego using these
tools. GCMs represent an important assessment procedure of potential effects on the global climate pattern,
but \\.e must maintain the proper perspective regarding
their limits.
Climate change is a natural aspect of the atmosphere and has been occurring since the beginning of
the earth. Moreover, il is likely that the atmosphere responds chaotically lo an imposed external (e.g. change
in solar constant.)or internal (e.g. increased greenhouse gases) change since \\'eather is a highly nonlinear
system. If a chaotic response occurs, the future slate
of the atmosphere to these changes would be unpredictable with a single GCM result. presenting just. one
possibility out of a spectrum of climate responses even
if all the physical processes were properly represented.
Even the Gaia hypothesis, in ~'hich Lovelock27 proposes that biological responses to changes in the environment damp the resultant net environmental change
may not accurately represent the actual respon~ of the
earth's atmoophere. Zeng (I 11/,28,for example, use the
\"atson and Lovelock29 example of a simplified Gaia
response (daisyworld) to show that if the interaction
between the biosphere and atmosphere is sufficiently
nonlinear. a chaot.ic response \\'ill occur.
11. POLICY RECOM:MENDATIONS
Since climate change is a natural feature of the earth,
\ve need to husband our resources even if there were no
man-caused changes (e.g. Schneider30). \\'ith respect
to man's potential influence on climate, the "path-ofleast-regret" is that ".e should immediately adopt policies which mitigate man's impact providing there are
no deleterious economic, environmental, or political effects of these policies. Even better, of course, is if these
policies result in positive benefits to mankind. C<>nservat ion of fossil fuel resources, for example, and utilization of renewable energy resources represent examples
of beneficial activities which should be promoted by
government policy makers regardless of the direction of
climate change. Recommendations by Rosenfeld and
lIafemeister31 represent definite steps \\.hich could be
taken to achieve this goal. Policies \\.hich require sig-
acknowl ged for their contributions to our investigation of t e influence of changes in cloud albedo on climate. P t of the work reported in this paper \\.as supported u der NSr Grant #ATM-861666'l and #ATM8915265. 1 Dallas McDonald ably completed the ~.ord
processing and editorial preparation of the manuscript.
13. REtERENCES
Ba
i astow,
R. and
sph ric carbon
C.D.
dioxide
set 'ed airborne fraction.
Keeling,
concentration
1981:
Atrno-
and the ob-
Carbon Cycle .\/ode/ling,
SC PE 16, B, Bolin, Editor, John Wiley and
So s, Chichester, 103-112.
2. Bof.n, B., B. R. 0008, J. Jager, and R.A. \,,'arrick,
Ed tors, 1986: The G~enhollse Efftct, Climatic
Ch nge, and Ecosystems, SCOPE 29, John Wiley and Sons, Chichester.
3. Ha sen, J. and S. Lebedeff, 1987: Global trends
of easuredsurface air temp~rat.ure. J. Geophgs.
Re .,92,13,345-13,372.
4. Jo es, P.D., S.C.B. Raper, R.S. Bradley, A.F.
Di ,P.M. Kelly, and T.~I.L. \\'igle,!, 1986a:~orth.
ern hemispheresurface air tempera! urevariations:
18 1-1984. J. Climate .4ppl ,\fetfor., 25, 161-
17.
5. JO~es, P.D.. S.C.B. ~aper, and T.~I.~. \"igley,
19 6b: Southern hemIsphere surface air temperat re variations: 1851-1984.
.~{ teor.. 25, 1213-1230.
J. Climate Appl.
6. Ka I,T.R.,J.D.Tarpley, R.G.Quayle, H.F. Diaz.
D. .Robinson, and R.S. Bradley, 1989: The rece t climate record: What it can and cannol lell
us. Rf.v. Gtophys., 27,405-430.
7. ~ fsnyder, W.E., 1989: A tale of ten fallacies:
T skeptical enquirer's vie,,' of the carbon dioxid Iclimate controversy. Agric. Fortst .\ftttor.,
47 349-371.
8. Lit Zen. R.S., 1990: Some coolness concerning
gl bal \\'arming.
pr
Bull.
Amer. Meteor. Soc., (in
).
Envirodmental Software. 1991. Vol. 6. No.2
105
9. ~Ijchacls, P., 1990: The greenhouse effect and
the global change: Revic\\' and reappraisal. Int.
J. Enl,iron.
Sluaits, (in press).
10. C-css,R.D., G.L. Potter, J.P. Blanchet, G.J. Boer,
S.J. Ghan, J.T. Kiehl, H. Le Treut, Z.-X. Li, X.Z. Liang, JF.B. ~Iilchell, J.-J. Morcrette, D.A.
Randall, M.R. Riches, E. Roeckner, U. Schlese,
A. Slingo, K.E. Taylor, W.M. \\'ashington, R.T.
\\'etberald, and I. Yagai, 1989: Interpretation of
cloud-climate feedback as produced by 14 atmospheric general circulation models. Scitnct, 245,
513-516.
Gulowski, W.J., D.S. Gutzler, and W.C. Wang,
1990: Surface energy balances of lhree general
circulation models: Implicalions
for simulating
regional climate change. J. Climate, (submil-
ted).
12. NOAA Report, December 11,1989, U.S. Department of Commerce, National Oceanic and Atmospheric Administration.
13. King, D.A., G.E. Bingham, and J.R. Kercher,
1985: Estimating the direct effect of CO2 on soy.
bean yield. J. Enriron. ,\Igt., 20, 51-62.
14. Rogers, H.H., R.D. Beck, G.E. Bingham, J.D.
Cure, J.M. Davis, W.\\'. Heck, J.O. Rawlings,
A.J. Riordan, N. Sionit, J.M. Smith, and J.F.
Thomas, 1981: Rtsponst of Vtgetation to Carbon
Dioxide. 005: Field studies of plant responses
to elevated carbon dioxide levels. Prepared for
DOE and USDA.
15. Pielke, R.A., 1984: .\fesoscale meteorological modeling. Academic Press, New York, N.".,
612 pp.
16. Pielke, R.A., 1988: E\'aluation of climate change
using numerical models. In "Monitoring Climate
for the Effects of Increasing Greenhouse Gas Concentrations. Proceedings of a Workshop". R.A.
Pielke and T. Kittel, Eds., Cooperative Institute
for Research in lhe Almosphere (CIRA), Forl
Collins, Colorado, August 1987,161-172.
17. Warren, S.G., C.J. Hahn, J. London, R.M. Chervin, and R.L. Jenne, 1988: Global dislribution
of total cloud cover and cloud type amounts over
the ocean. Prepared for the United Slates Department of Energy, Washington, D.C. and lhe
Nalional Cenler for Atmospheric Research, Boul-
der, Colorado.
18. Pielke, R.A. and R. Avissar, 1990: Influence of
landscape structure on local and regional climate.
Landscape Ecology, (accepted).
106
Environmental Software. 1991,Vol. 6, No.2
19.! Rosenberg,
N.,
ica/ Enrironmcnt.
19i4:
.\/Icroc/imatc:
\\'iley,
~e'"
Tllc
lliolog"
York.
20, Segal, M" R. A,'issar, M.C, '{cCumber, and R.A.
Piclke, 1988: E,'aluation or ,'egetation effects on
the generation and modification or mesoscale circulations. J, A/mos, Sci., 45, 2268-2292,
21. Segal,M., W. Schreiber, G. Kallos, R.A. Pielke,
J.R. Garratt, J. Weaver, A. Rodi, and J. Wilson, 1989: The impact of crop areas in northeast
Colorado on midsummer mesoscalethermal circulations. Mon. ~f'ea. Rtv., 117,809-825.
22. Pielke, R.A. and X. Zeng, 1989: Influence on severe storm development of irrigated land. JVai/.
~f'eG.Dig., 14,16-17.
23. Two~y.l S., R. Gall, and M. Leuthold, 1987:
Pollution and cloud refle<lance. In "Interactions
Between Energy Transformations and Atmospheric Phenomena. A Surveyof RecentResearch"
M. Beniston and R.A. Pielke, Eds., D. Reidel
Publishing Company, Dordre<hl, Holland, 335348.
24. ! Sansom,J., 1989: Antarctic surface temperature
time series. J. Climate, 2,1164-1172.
25. Schlesinger.M .E., 1988: ~fodel projections of the
equilibrium and transient climatic changes induced by increased atmospheric CO2. In "Monitoring Climate for the Effecls of Increasing Greenhouse Gas C~ncentrations. Proceedings of a
\\'orkshopft. R.A. Pielke and T. Kittel, Eds.,
Cooperative Instilute for Researchin the Atmosphere (CIRA). Forl C~llins. Colorado, August
1987.3-50.
26. Michaels, P.J., D.E. Sappington, B.P. "ayden,
and D. Stooksbury, 1988: Nonthermometric measurement of recent temperature variability over
the coterminous United Slates, southern Canada,
and Alaska. In "Monitoring Climate for the Effects of Increasing GreenhouseGas C-oncenlrations. Proceedings of a "'orkshop". R.A. Pielke
and T. Kittel, Eds., Cooperative Institute for Research in the Atmosphere (CIRA), Fort Collins,
Colorado, August 1987, 119-134.
27. Lovelock, J.E., 1982: Gaia as seen through the
atmosphere. Biominerali:ation and biological
mctal accumulation(Eds. P. Westbroekand E.W.
de Jong). D. Reidel Publishing Co., Dordrecht,
The Nelherlands, 15-25.
28.1 Zeng, ~., R:A. Pielke, and R. Eykholt, ]990:
Chaos In Dalsy\\.orld.
rt//us, (accepted).
OrtrlocItd'
Scitntlfic
{.!.!ut.!: R.A. P,tlit
29. Watson, A.J. and J E. Lovelo<k, 1983: Biological homeostasis of the global environment: the
parable of daisy".orld. Te/lus, 35B, 284-289.
30. Schneider, S,H., 1976: The Genesisstrategy: Climale and global survival. Stephen H. Schneider
\\'ilh Lynn E. Mesiro\\', Plenum Press, New York.
31. Rosenfeld, A.H. and D. Hafemeister, 1988: Energy efficient buildings. Scientific A mencan, 258,
78-85.
Envirohmental Software, 1991,Vol. 6, No.2
107
Errata
R.A. Pielke
In Pielke (1991), a factor of 4 was left off of equat
applied to global average conditions. For local daytim
scaling form provided. S is modified to represent the
and time of year. The more appropriate heat budget
importance of albedo change is
on (1) when this
evaluations, it is
olar radiation at
quation to use in
relation is
the correct
that locale
scaling the
With this correction equation (2) becomes
~TE = -67 ~A
So that a +3% change of albedo over the oceans wo~ld yield an equilibrium temperature change of more than -I.5°C. The equation inlSection 6 should then read
~Te = -176A
so that a land-average increase of SA of 1 % would reS1
lt
temperature
spond
of
-O.17°C.
A
decrease
of
1%
would
corr
in
a
change
to
a
of
O.17°C
equilibrium
warming.
Similarly, a 25% change in land surface albedo over % of the land surface would
yield the same result.
f
In Section 8, the correction of the original equation (2) O (C2) results in an increase
in albedo of 10% over 10% of the Earth's surface woul result in a decrease in T e of
O.67°C.
The conclusion of the Pielke (1991) paper is not affect
clear from even this simple analysis that even relativel
characteristics (in this case albedo) can have an imp
nificant as the hypothesized enhanced warming cause
d by these corrections. It is
small changes in landscape
ct on global climate as sigby anthropogenically input
greenhouse gases.
References
Pielke, R.A., 1991: Overlooked scientific issues in asses~inghypothesized greenhouse
gas warming. Environ. Software, 6, 100-107.
I