Dan Pangburn: Cloud Altitude Change Causes Global Temperature Change

Posted: June 29, 2011 by Rog Tallbloke in climate, Energy, Ocean dynamics

The temperature range of the 20th century spans about 0.74 C. Of this, about 40% or 0.3 C
has excellent correlation with the sunspot time-integral. An equation has been derived
that calculates average global temperature based on the physical phenomena involved.
With inputs of accepted measurements (source web links are given) from government
agencies, it calculates the average global temperatures (agt) since 1895 with 88.4%
accuracy (87.9% if CO2 is assumed to have no influence). This research is presented at
Reference 1 and links given there.

Clouds radiate energy from the planet. Cloud elevation determines cloud temperature and
thus the energy rate. The analysis presented here determines that an increase in average
cloud altitude of only about 72 meters results in an increase of steady-state average global
temperature of 0.3 Celsius degrees. Svensmark2 has shown that more sunspots correlate
with fewer low-level (below 3 km) clouds. If there are fewer low-level clouds then
average cloud altitude must be higher, average cloud temperature lower, less energy
radiated from the planet and thus the planet warms.

Steady-State Energy Balance
The overall approach is to determine base values that balance energy flows and then to
determine how each of these values must change in response to a change in average cloud
temperature.

As a starting point in the analysis, the flow of energy is determined partly using estimates
from other sources, some rational refinements, and conservation of energy
considerations. A graphic that was copied from a NASA site3 is useful as a qualitative
description of the various energy flows. It is shown below with some revisions. Some
energy flows are more explicitly defined than at the NASA site and the values presented
there are replaced by symbols (alpha characters) with values determined herein.

Svensmark2 determined that more sunspots resulted in fewer low level (<3 km) clouds. If
there are fewer low-level clouds then the average cloud altitude would be higher. This
gives rise to the question that is addressed in this paper of how the steady-state surface
temperature would be influenced by change to average cloud altitude.

The general approach used here to determine this is to establish a baseline of values that
balance energy flows on the above graphic and then to determine how the surface
temperature changes as the cloud temperature changes.

The following demonstrates that higher average cloud altitude would result in increasing
average global temperature as occurred during the solar grand maximum of the last half
of the 20th century. All energy rates are in watts per square meter.

Calculation of the Magnitudes of Energy Flow
Measured values of energy from the sun vary only slightly depending on the solar cycle
and slight other long-term variations in the ‘solar constant’. The value used here is 1365
W/m2. The energy from the sun is intercepted by the planet according to the cross section
area but is distributed according to the surface area so this is divided by 4 to account for
the ratio of surface area to cross-section area of a sphere.

Q = 1365/4 = 341.25 W/m2
Part of this incident energy is reflected. The fraction of the incident energy that is
reflected is often assumed to be determined by the earth’s albedo which, from what
appears to be a credible source4, is about 0.297. However, albedo is primarily diffuse
reflection and does not include Fresnel-type low-incident-angle specular reflection8 from
the 71% of the planet that is covered by water. The fraction of the total energy reflected
from the planet is slightly higher than that determined by albedo alone and is about 0.308
(my calculation).
R = Q * 0.308 = 105.105 W/m2

The amount of energy reflected from the clouds and atmosphere was determined as
required to maintain the same ratio of cloud+atmosphere reflection to surface reflection
as is reported by Kiehl and Trenberth5.
A = R/(1+23/79) = 81.4 W/m2

Part of the remaining energy is absorbed by clouds and atmosphere. I selected a value of
48% for this to be consistent with the absorbed energy rate assessment by Kiel &
Trenberth5. A comparison of the 1997 and 2008 K & T values along with corrections are
shown on page 3 of Ref 6. An additional factor of 0.6 accounts for the observation that
clouds cover about 60% of the planet.

B = (Q-A) * 0.48 * 0.6 = 74.84 W/m2
The energy that gets through the atmosphere is simply that which is not reflected or
absorbed by the clouds and atmosphere.
C = Q – A – B = 185.01 W/m2.
The part of this that is reflected by the surface is simply that part of the total reflection
that was not reflected by the clouds and atmosphere.
D = R – A = 23.71 W/m2.
The energy that is absorbed by the surface is the part of C (the entering energy that got
through the atmosphere) that is not reflected.
E = C – D = 161.31 W/m2.
The energy leaving the surface as convection (thermal), evaporation (latent) and radiation
from the surface that directly leaves the planet are all as presented on the K & T chart.
F = 17 W/m2
G = 80 W/m2
J = 40 W/m2

The radiation from the surface is gray-body radiation as calculated by the Stephan-
Boltzman equation. Most (71%) of the surface of the planet is covered by sea water with
an emissivity of about 0.995 at water temperature. Part is from snow with emissivity of
about 0.99 and the rest is from land that is mostly about 0.99 but with a few small local
areas that are substantially lower. The over-all average emissivity from the surface is
taken to be 0.99. The average global temperature is taken to be 288 K as typically
reported. The S-B constant, σ, is 5.6697E-08 W/m2/T4. (Temperature in degrees Kelvin)
U = 0.99 * 5.6697E-8 * 288^4 = 386.16 W/m2

Clouds are fine particles of liquid water or ice and thus also radiate according to the S-B
equation. Clouds cover about 60% of the planet and have an average emissivity7 of about
0.5. Their average temperature was determined to be 258 K in an entirely different
analysis that produced an average global temperature of 288K. The thin air and low
temperature at high altitude means that there is very little water vapor so radiation up
from the clouds nearly all gets directly to space. The small part that doesn’t is ignored
resulting in:
P = 0.6 * 0.5 * 5.6697E-8 * 258^4 = 75.36 W/m2.
The same energy flux as from the top of the clouds exists also from the bottom of the
clouds. The down flux encounters substantial absorption prior to reaching the ground.

K & T report 40 W/m2 or 40/396 = 10.1 % of the radiation making it from the surface
through the ghg to space. A calculation using data from Barrett9 for 60% cloud cover
produces 10.8 %. Since about half of the source radiation is stopped by clouds in going
from the surface to space and not stopped by clouds when going from clouds to the
surface, the fraction getting to the surface is about 21% of that going from the surface
directly to space.
K = 0.21 * P = 15.83 W/m2.
The total energy being radiated from the planet must be the amount from the sun minus
the amount reflected.
M = Q – R = 236.10 W/m2.
The energy radiated from the atmosphere must be the total for the planet minus that just
from the clouds to space minus that which goes directly from the surface to space.
N = M – P – J = 120.78 W/m2.
The amount of energy that is thermalized can now be calculated from the other values
entering and leaving the atmosphere system.
H = M – J + K – F – G – B = 40.13 W/m2.
The fraction of radiation from the surface (that does not go directly to space) that is
thermalized is
TH = H/(U-J) = 0.1159 or 11.59%.
The energy that is absorbed by ghg and returned to the surface is that leaving the surface
minus that going directly to space minus that which is thermalized.
I = U – J – H = 306.02 W/m2.

Effect of cloud altitude change
Cloud temperature varies with altitude and, on average, varies as presented in the
Standard Atmosphere Tables that are widely available. Using the graphic above and the
values calculated above as a baseline, required cloud temperature change to produce a
given surface temperature change was determined.
The new value for the amount of energy that is thermalized starts with the baseline value.
Adjustments are made to it to account for changes to the other values entering and
leaving the atmosphere system. Subscript 0 refers to baseline values, s refers to surface
and c refers to cloud
H = H0 + (N – N0) – (F – F0) – (G – G0) + (K – K0)
Thermalization does not change so it is used to determine the new value for the energy
radiated from the surface.
U = H/TH0 + J

Each of the baseline values of energy rate was varied according to a function of a new
temperature to the baseline temperature as follows:

The above numerical data for the steady-state average global (surface) temperature that
results from change in average cloud altitude is shown in the following graph:

This graph is actually slightly curved. It appears to be straight because it covers such a
small range, although the range is large compared to the magnitude of change in average
global temperature that has actually been experienced since accurate temperature
measurements have been made.

As previously determined1 the part of agt change that is not accounted for by effective sea
surface temperature change and the tiny bit that might be attributed to the change in the
level of atmospheric carbon dioxide is about 40% of the total or about 0.3 C. A cloud
average altitude change of only about 72 meters results in this amount of steady-state
average global temperature change.

References:

1. http://climaterealists.com/index.php?id=7359

2. Phys. Rev. Lett. 85, 5004–5007 (2000) (a very brief summary is at

http://prl.aps.org/abstract/PRL/v85/i23/p5004_1)

3. http://earthobservatory.nasa.gov/Features/EnergyBalance/page6.php

4. http://adsabs.harvard.edu/abs/2001GeoRL..28.1671G

5. http://chriscolose.wordpress.com/2008/12/10/an-update-to-kiehl-and-trenberth-1997/

6. http://climaterealists.com/attachments/database/corroborationofnaturalclimatechange.pdf

7. http://www.arm.gov/publications/proceedings/conf08/extended_abs/shippert_tr.pdf

8. http://en.wikipedia.org/wiki/Reflectivity

9. http://www.warwickhughes.com/papers/barrett_ee05.pdf

Comments
  1. vukcevic says:

    It is possible that there is a cause-consequence interchangeability here (proverbial chicken and egg relationship).

  2. Thierry says:

    Hello everybody.

    I am quite sorry to say that this analysis is totally meaningless. Since Gerlich & Tscheuschner in their famous “‘Falsi fication Of The Atmospheric CO2 Greenhouse Effects Within The Frame Of Physics” showed that back radiations can not exist and earth energy budget can not be assessed based on simplistic Stephan-Boltzman equation use, this kind of approach can not prove anything.

    Even NASA has removed greenhouse gas back radiation from it’s latest diagram of the earth’s energy budget:

  3. tallbloke says:

    Hi Thierry, NASA show a ‘net’ radiation figure on their latest diagram.

    http://tallbloke.wordpress.com/2010/11/16/whatever-happened-to-back-radiation-part-ii/

  4. Stephen Wilde says:

    I can see that a variation in the relative quantities of low as against high clouds could provoke different thermal responses.

    However I’m not convinced that that necessarily has any bearing on the Svensmark hypothesis that more cosmic rays during a period of less active sun provoke more clouds by supplying more condensation nuclei.

    I think it far more likely that variations in solar activity alter the atmospheric heights so as to shift the surface air pressure distribution.

    Hence more zonal/poleward jets when the sun was active and more meridional/equatorward jets when the sun is less active as now.

    Increased meridionality in the jetstream paths would lengthen the air mass boundaries, enhance mixing of air over larger areas and create more clouds. More equatorward jets would have the same effect.

    Such processes would also alter the relative quantities of low as against high clouds because increased air mass mixing at the surface would tend to create lower clouds rather than higher clouds. The latter would be a result of more convection rather than surface air mass mixing.

    So, subject to further investigation I think I have a more plausible scenario than does Dr. Svensmark.

  5. tallbloke says:

    Stephen, I’m inclined to agree, and the correlation I found between solar activity and upper tropospheric specific humidity adds evidential support I think. However, since both the Svensmark effect and the humidity effect both tend in the same direction, this study could still be a valuable contribution.

  6. Tim Channon says:

    “Clouds radiate energy from the planet.”

    Dispute.

    Clouds form as a result of energy release by water phase change from gas to liquid. ie. are visible evidence of past energy movement.

  7. Tim Channon says:

    Back radiation.

    That is a storm about nothing as such, a perfect valid concept _in correct context_ but that is not the case, is cherry picking.

    You can deal with body temperatures.
    You can deal with the consequences of body temperatures.
    Do not mix.

    Basically back radiation is about the energy interchange between bodies, a necessary consequence of the speed of light. A body has zero knowledge of what is coming and will emit regardless, hence a radiation balance of in and out which is the same thing as two bodies with a temperature.

    Why the AGW mob love back radiation?

    The atmospheric gases are a nebulous entity which is ethereal, you cannot point to a body, cannot stick a thermometer in it. This is what in a different field we call a parasitic body, is notional but interrelated with real bodies.

    Switch to back radiation from a something. Unfortunately this is very dodgy, is uncontrolled and undefined. Worse and I think critical, the same body is receiving input from the sun, hence the attempts to hide the fact that the sun radiates stronger than the earth at ghg wavelengths.

  8. Where I used to work they had a 6 feet square hot solvent tank, with a refrigerated top edge to re-condense the vapor to keep it in the tank, about 4 feet down to the fluid and 3 feet of depth filled with baskets filled with parts to be cleaned of oil residue before chrome plating.

    The top of the condensing vapor looked much like a cloud top, and as we would add cold new parts the top of the vapor would drop as the thermal energy would flow into the brass parts (have high heat conduction rate) the top of the cloud would clear a way so you could see what was going on in the bottom. When we would pull the cleaned parts up part way to drain, for a few seconds, then hoist the baskets up to the center of the upper edge and let the vapors fall off into the condensing area, and go back to the bottom.

    I can see how the vapor pressure, ion content, dew point background changes that results in the ambient temperature at the base of cloud formation being what it ends up, as an interaction of these and solar energy input pressures to give resultant cloud height and heat loss characteristics seen as described above, with out the mention of the ion content.

  9. It is when you add in the consideration for the ion content, that you see cloud height characteristics modified in density of the cloud cover from more or less condensational neculi coming in from space, as well as the static/ionic charges on the parcels of air masses, from meridional flow mixing of the areas between the Equatorial Jets and the Polar Jets when resonate tidal interactions peak at nodal cycles.

    The combination of the self regulating system just shifts to a new equilibration level, needed to balance the total combination of inputs to the system at this time, the weather is that regulation system, the only missing details is how it all fits together.

    Richard Holle

  10. tallbloke says:

    If anyone is smart enough to understand it, (I’m sure Richard Holle is), Brian Tinsley’s work on the global electrical circuit and clouds will be highly relevant here.

    http://www.utdallas.edu/physics/pdf/Tin_rev.pdf

  11. Tenuc says:

    Good post, but I find think looking at just one process at a time doesn’t prove how the Earth’s homoeostat operates to keep temperature on the surface long-term stable to with just a few degrees. I deliberately avoid the word ‘balance’ as climate is a turbulent dynamic system and energy in and out is varying at any moment in time. Also, because of the turbulence and large number of complex inter-linked sub-systems, climate cannot display any statistical average behaviour at any time scale. Like Stephen Wilde, I think that we will only get an understanding of how things work by adopting a top-down approach and that trying to quantify the Earth’s energy state is at best a fools errand and at worse allows one to reach conclusions which verify one’s own beliefs – it becomes just a garden for cherry pickers!

    Tim Channon says:
    June 30, 2011 at 12:21 am
    “…Why the AGW mob love back radiation?

    The atmospheric gases are a nebulous entity which is ethereal, you cannot point to a body, cannot stick a thermometer in it. This is what in a different field we call a parasitic body, is notional but interrelated with real bodies…

    Yes! How can a law designed to work for a solid perfect emitter in a vacuum be applied to our turbulent dynamic unbounded (between land/sea & magnetosphere) atmosphere and be expected to provide sensible linear results?

    Richard Holle says:
    June 30, 2011 at 5:43 am
    “It is when you add in the consideration for the ion content, that you see cloud height characteristics modified in density of the cloud cover from more or less condensational neculi coming in from space, as well as the static/ionic charges on the parcels of air masses, from meridional flow mixing of the areas between the Equatorial Jets and the Polar Jets when resonate tidal interactions peak at nodal cycles.

    The combination of the self regulating system just shifts to a new equilibration level, needed to balance the total combination of inputs to the system at this time, the weather is that regulation system, the only missing details is how it all fits together.”

    Totally agree Richard. To get to “how it all fits together” is currently beyond the sphere of our wisdom. Even if we had the knowledge to be able to identify all the inputs to our weather/climate system and the capability to measure it at a sufficiently good data granularity we have yet to develop the mathematical tools to produce even reasonable quantified estimates of energy in and out.

    I’m busy today, but will come back to this thread with a broad-canvas qualitative sketch of some of the issues real climate scientists need to work on.

  12. Just read Brian Tinsley’s pdf for the third time and he lays out the electromagnetic/electronic circuitry you would need to plug in the values of flux movement of the underlying solar wind coupled magnetic activity to get numbers that could help gauge how much input from each of the “A, B, and C inputs” to derive an understanding of the shares of the components added to make the whole effects seen.

    Before I read his work I was convinced that there was a way the changes in solar wind and density from the occurrence of a heliocentric or Synod conjunction with the electro-scavenging of ions, due to the input of the increased corresponding magnetic flux being carried on the solar wind. Brian T gives the circuit diagram and method for calculating the separate sources of ions being available, scavenged, or produced if the real values of the changes in Jz or total electromagnetic flux from the solar wind input were known over the whole area of the Earths magnetosphere.

    I am not holding my breath for the new data from the THEMIS satellites to be made public in a format we can work with easily. I do how ever look forward to the time when the outer two are deployed and stable orbiting around the moon. These data fixed to source area of the moon will reflect the signals generated by the Earth Moon interactions from a common vantage point reference, and should give nice ball park figures of the flux from lunar phase shifts as well as declinational shifts.

    I have been hoping to find in that new as yet unknown set or patterns seen from that vantage point as the proof of the 27.32 day cyclic effects and the lunar declination and solar magnetic rotation synchronization to be one of the things that “surprises scientists” when they stumble upon the patterns, that should be as obvious as your freshly hammered thumb.

    From out of that noise should appear the electromagnetic effects of the outer planets Synod conjunctions, and perihelion/ aphelion cycles. The blending of these effects with the current inner planet 6558 day Saros cycle -27.32 days to make an even 240 lunar declinational cycles, should fill in the rest of the signal that is missing from the 6558 day pattern alone.

    These outer planet synod cycles excursions from the inner planetary affected weather are the extreme excursions that Piers Corybn catches, that as yet I have not derived a good algorithm to add to my 6558 day method to get the finished product right. But in the same vain Piers and Ulric still don’t see the utility of the lunar declinational tides, more swamp to cross, hills to climb, road to travel, gives me more will to live longer.

    Earl Happ will be flexible enough to incorporate the electromagnetic drivers found into his polar charge shifting process, Lief not so much I think.

  13. Tenuc says;
    Totally agree Richard. To get to “how it all fits together” is currently beyond the sphere of our wisdom. Even if we had the knowledge to be able to identify all the inputs to our weather/climate system and the capability to measure it at a sufficiently good data granularity we have yet to develop the mathematical tools to produce even reasonable quantified estimates of energy in and out.””

    Like any periodic harmonic interaction that has repeating patterns, you don’t have to have the real values for each separate piece of the mechanism, if the resonate frequency and modulation patterns are known, the driven effects will repeat, and as you find the answers to each part of the puzzle that can be solved directly, and substituted into the equation the unknowns become indirectly defined.

    Inductive reasoning from following patterns, and known laws coupled with deductive reasoning of the values of segments of the composite that can be studied, in electronics is all we have to solve the normal range of problems engineers see daily, and it works for them. Segmentation, solution then reintegration to redefine the residual problems is the way progress is made in design engineering new ideas, TV’s, Cars, Large ore trucks, nuclear weapons, the same will continue to be applied to the solar system and how it works. I just want to be close enough to see it happen clearly.

  14. Tim Channon says:

    Some food for thought on surprising effects when things are moving and including the sheer complexity where no-one is quite sure.

    http://en.wikipedia.org/wiki/Shower-curtain_effect

  15. Tenuc says:

    Richard Holle says:
    June 30, 2011 at 11:03 am
    “…Inductive reasoning from following patterns, and known laws coupled with deductive reasoning of the values of segments of the composite that can be studied, in electronics is all we have to solve the normal range of problems engineers see daily, and it works for them…”

    As of the present this is my feeling too. Trying to pin down good quantitative data can only produce puzzling and misleading results which can easily be ‘massaged’ to support ones own beliefs. For now, the heuristic approach using patterns seen in large-scale sub-systems seems the best way forward. However, how these patterns change over 100y climate scale periods remains to be seen.

  16. Lord Beaverbrook says:

    A quick dumb question from a non scientist:

    Didn’t NASA release a study that stated in times of a quiet sun that the Earths atmosphere shrinks with the magnetosphere. Wouldn’t this automatically affect the altitude of clouds?

  17. vukcevic says:

    Tim Channon says: June 30, 2011 at 11:47 am
    Some food for thought on surprising effects when things are moving and including the sheer complexity where no-one is quite sure.

    http://en.wikipedia.org/wiki/Shower-curtain_effect

    On the shower curtain effect:
    Water is dielectric, droplets moving through air get electrically charged, shower curtain is usually synthetic and insulator.
    Here is a demo of the moving water – insulator interaction :

  18. Tenuc says:

    And here’s another one – Water Repelled by a Magnet.

  19. tallbloke says:

    Lord B: The thermosphere shrank by 30% in the recent solar minimum according to NASA. It’s a very tenuous gaseous layer, but it probably has some effect on the stratosphere at least. And the stratospheric changes affect surface level pressure systems…

  20. tallbloke says:

    Peter Taylor says:
    July 1, 2011 at 4:47 am

    Its frustrating, as a member of the ‘sceptic’ community, to write a whole book on this issue that so few people in this community appear to read! As far as I know, Anthony, you have never mentioned it! Any reasons? In ‘Chill: a reassessment of global warming theory’ you will find all of this rehearsed with full references to the peer-reviewed literature. You wonder whether the ‘dip’ from 1970 wasn’t created by aerosols….it was, but not by human sources as in the IPCC range of models (mostly sulphates) – see below:

    yes, to Henry P. – there is clear evidence that the recent global warming is largely natural – and it comes from three papers in Science during 2005 (Wild, Pinker and Wielicki – referenced in Chill) which found:

    * that ‘global dimming’ was truly global and occurred in pollution free zones such as the southern Pacific – this was later admitted in IPCC-2007, though well-buried, hence all the models that used anthropogenic sulphur to explain the dip were erroneous;
    * the ‘brightening’ was also global and even occurred in China, despite the pollution there – and it began BEFORE the major initiatives to reduce sulphur emissions took effect…these were only ever of local significance in relation to atmospheric budgets – the brightening (increased insolation at the surface of the earth and oceans) occurred also in cloud-free measurements, hence indicating increased transparency of the atmosphere (there were also lower cloud levels…4% reducation from 1980-2000).
    * sulphur abatement was in any case only regional, the emissions of Asia made up for the reductions in the West….global sulphur flatlines from 1980-2000, and in any case is it is emitted effectively at about 100m it is not likely to affect the relation of atmospheric/surface temperatures as in the case of a major volcanic eruption (as per the models).

    The 1950-1980 ‘dip’ in global temperatures and the erroneous treatment in models represents a huge error on the part of ‘warmist’ thinking and modelling, yet it is effectively covered up…even more effectively when none of the critics reads the critical science!!!

    You will find detailed analysis of the surface insolation data…due to lower reflective cloud cover and more transparent atmosphere, there was a roughly 4 watts/square metre excess Short Wave radiation running from 1980-2000 compared to 1 watt/square metre Long Wave computed for CO2. Being generous, the extra GHG could account for 20% of the warming – unless you argue that CO2 managed to thin the clouds as a feedback…which has been argued, despite the improbability. If that were the case, then post 2000 you would expect the trend to continue – it did not, cloud cover came back by 2%, ocean heat storage flatlined and so did sea-level rise.

    And regarding the reason why the northern hemisphere heats up more than the south – that is also in the book: it is because 80% of global warming heat is held in the upper 200m of the ocean and then released to land…to be ‘held’ it has to be stored and this takes place in two major gyres in the north Atlantic and north Pacific…these are formed as the ocean’s coriolis force is constrained by the northern continents. In the souther hemisphere there is no such constraint and the circumpolar current dissipates the heat as it moves southward from the equatorial regions.

    This heat storage is therefore not global, but regional. It is subject to long term cycles such as in the MWP/LIA dictated I suspect by the location of the jetstream, insulating cloud, and heat-extractive vortices (cyclones). The location of the jetstream is sensitive to the solar magnetic cycles as a proxy for UV output.

    Carbon dioxide is, of course, a GHG and will contribute to these natural cycles but there is little empirical evidence that it amplified natural cycles in the Holocene, and no statistical treatement yet published to show that it did so during the glacial/deglacial episodes either – its effect is too weak. As we enter what may become the next Maunder Minimum (also treated in the book), CO2 ‘s weak effect might just save us from tipping into the next ice-age! But don’t try and tell Greenpeace!

  21. Peter Taylor says:

    Thanks for posting over from WUWT…I would like to add, I am convinced that the major swings in the ice-core records, especially in Greenland, are determined by wind changes, which determine then ocean currents and cloud patterns as well as cyclic storage of heat in the ocean’s top 200m – nothing else can act that quickly…the rises are very quick indeed.

    These changes in wind patterns could be entirely explained by studying the jetstream behaviour of the last 3-4 years of the current solar minimum and low cycle 24. A percentage shift in winds over the heat stores of the northern gyres is enough to swing the decadal cycle and enough to account for abrupt (almost annual) temperature changes in the GISP record.

    Of course, this is not the same as a global shift….and I want to get a better handle on the relation of NH change with SH and Antarctica.