Meteorologists are well aware that surface temperature varies with geopotential height at 500 hPa. The United States National Oceanic and Atmospheric Administration says as much below. The full text can be accessed at: here:https://www.ncdc.noaa.gov/sotc/global/201507
But hey, there is a problem here: The text above the map states that there is a relationship between geopotential height at 500 hPa and surface temperature. But thereafter, the commentary is driven by an overarching belief that carbon dioxide drives surface temperature and it is therefore constantly escalating.
But carbon dioxide is well mixed in the atmosphere and cannot account for regional warming on a month by month basis. The observed warming is regional in scope and it conforms to the pattern of the distribution of surface pressure and geopotential height, not the distribution of carbon dioxide that is in fact well mixed and very close to uniform in its distribution throughout the atmosphere.
And surface temperature is not constantly escalating as we will see below.
Gordon Dobson started measuring total column ozone in 1924 and soon noticed that total column ozone mapped surface pressure. An increase in surface pressure that is related to the distribution of ozone can originate in two ways namely:
- A reduction in the ozone content of the column above 500 hPa allowing the upper half of the column to become more dense, contract and thereby allow more molecules to populate that column. But, this is not possible in a column of descending air that has its upper extremity in the stratosphere.
- A piling up of atmospheric mass against the force of gravity in the mid latitudes due to a shift in mass from high latitudes. The density of the column in the mid latitudes is increased as atmospheric mass accumulates.This should reduce geopotential height at 500 hPa. For geopotential height to increase at 500 hPa the increase in atmospheric mass must be accompanied by warming below the 500 hPa pressure level . The lower half of the column becomes less dense as the column weight increases.
So, the question arises, is the increase in geopotential height at 500 hPa due to the descent of ozone within the atmospheric column of descending air as the weight of the column increases?
SCRUTINY FROM ABOVE
When satellites were equipped to study the atmosphere in 1969 ozone could be mapped more effectively than via surface measurement. The following report of 1973 links the distribution of ozone to geopotential height at 200 hPa :
Plainly total ozone varies with the upper troposphere (200 hPa) geopotential height, and ozone distribution at that level defines the circulation of the air and the jet streams.
If you have read chapter four you will be alert to the fact that south of about 20° of latitude ozone begins to affect the lapse rate at the 300 hPa level and that the notion of a demarcation between troposphere and stratosphere via a hypothetical ‘tropopause’ is no longer sustainable. Perhaps it is the fuzzy boundary phenomenon that leads to the ambiguity of lumping together the ‘systematic variation in ozone distribution in lower stratospheric circulation‘ and the ‘correlation between ozone and upper troposphere geopotential height’ in the abstract above.
The variation in ozone partial pressure drives geopotential height at 200 hPa. Of this there is no doubt. But, does it drive height at 500 hPa? The study reported below bears on this matter.
The authors of this study set out to examine the distribution of winter geopotential height minima over the period 1958–2006 at the 200, 500, and 850 hPa pressure levels. In effect they engaged in a very extensive mapping exercise to locate cyclones of ascending air that are associated with low surface pressure at three pressure levels, 850 hPa close to the surface, 500 hPa at the mid point and 200 hPa that is plainly within the fuzzy boundary between the troposphere and the stratosphere. When the geopotential height at a central point was lower than six or more of the surrounding eight points on a 2.5° latitude and longitude grid the authors nominated that point as a minimum of geopotential height and mapped it as seen above.
The map reveals that height minima at 500 hPa and 200 hPa have a common geographical distribution. Furthermore, in the lowest map we see an extension of the relationship into subtropical latitudes that sees variations of geopotential height at 850 hPa to some extent aligning with those at higher elevations.
In the light of this knowledge we might say that the temperature of the surface of the Earth is as much tied to variations in geopotential height at 200 hPa as it is to variations in geopotential height at 500 hPa and the implications would be very much clearer.
Lets pause at this point to remind ourselves of the very simple relationship between the capacity of the air to hold water vapour and its temperature. If the temperature increases more water can be held in the invisible gaseous phase. If temperature increases the droplets of moisture and highly reflective multi branching crystals of ice that constitute clouds will simply disappear. When this occurs the surface of the planet receives more solar radiation and it warms accordingly.
Lets pause a moment longer to observe that this very different chain of thought is the narrative that should follow the observation that surface temperature is related to geopotential height…… and I hope that the United States National Oceanic and Atmospheric Administration takes note and changes their narrative accordingly.
The critical observation is that geopotential height minima have a common distribution throughout what we refer to as ‘the troposphere’ and are forced by one means or another by differences in the ozone content of the air at the 200 hPa level and above. Many meteorologists being the practical, results oriented fellows that they are, have long noted that cyclogenisis at elevation seems to be a requisite for the development of cyclogenesis below.
Meteorologists examine the circulation of the air at 500 hPa to be relatively free of the influences of topography, vegetation, land and sea, in order to predict the course of weather in the days ahead. We see that the action at 500 hPa is plainly dictated at 200 hPa and above (the lower stratosphere) where the largest variations in geopotential height, ozone partial pressure, atmospheric density and air temperature are observed. But, is that the end of it?
CHANGE IN HIGH LATITUDES DRIVES CHANGE IN LOWER LATITUDES
Chapter 5 identified the origin of so called ‘cold core’ Polar Cyclones in the heating of the air above 500 hPa by ozone. A shift in atmospheric mass from high to mid latitudes is forced by enhanced cold core Polar Cyclone activity that drives surface pressure lower in high latitudes. The result is enhancement of surface pressure in the mid and low latitudes.
This chapter establishes that geopotential height at 200 and 500 hPa vary together in the extra-tropical latitudes. Furthermore, the increase in geopotential height that accompanies the surface pressure change is accompanied by a loss of cloud cover. All ultimately relate to the changing flux of ozone in the upper half of the atmospheric column in high latitudes that occurs in winter that drives both the exchange of atmospheric mass and the observed change in the distribution of ozone that drives the circulation of the atmosphere at 200 hPa in the extra-tropical latitudes.
We are aware that high pressure cells bring air from aloft towards the surface. We are also aware after chapter 5 that the stratospheric circulation involves descent in the mid latitudes. That brings air with an elevated ozone concentration into the troposphere.
Soooooooo, in the absence of an ability to touch, feel, smell or see what is actually happening in the atmosphere and with a sense of caution related to the fact that our hand waving and speculation is not always related to reality, and that we don’t always get things right we should inspect the surface temperature record for date stamping that is related to ozone flux at one pole or the other during the winter season. That should go a long way towards settling the matter, at least until a better explanation comes along……you know, I don’t think the science is ever completely settled.
THE SIGNATURE OF OZONE VARIABILITY THAT IS DATE STAMPED ON THE SURFACE TEMPERATURE RECORD
The tropics constitute a large surface area and make a huge contribution to the global temperature average especially on multi-year ENSO time scales. But surface temperature is actually most volatile on a monthly basis in the mid and high latitudes where ozone directly regulates cloud cover.
It is in the tropics that the waters of both hemispheres are brought together and homogenized. We can eliminate short term variability due to wind by looking at decades rather than years.
In the diagram below we have sea surface temperature at decadal intervals. Tropical sea surface air temperatures in April, May, June and July behave as if they were a bundled package with little variation between months. Departures seem to occur only when there is a marked change in trend. The month of April shows more variability and July the least.
By contrast, we see in the graph below, drawn to the same scale, that there is a big variation in air temperature between August and March. It is between August and March that polar processes engineer large changes in surface temperature according to the flux in ozone from month to month, year to year, decade to decade and across the centuries. Pre-eminent in terms of volatility are the months January February and March and to a smaller extent December, under the sway of Arctic polar processes. The Arctic, precisely because of the limited descent of mesospheric air is supercharged with ozone. When change occurs it’s dynamic. Its like coming into a perfectly dark room and switching on the light.
Source of data: http://www.esrl.noaa.gov/psd/cgi-bin/data/timeseries/timeseries1.pl
Antarctic atmospheric processes that involve the same interaction with mesospheric air as in the Arctic, but on a much more continuous and interactive basis, are most volatile between August and November. The movement in tropical sea surface temperature in these months is in the same direction at the same time but has less vigour in line with the reduced partial pressure of ozone in the entire southern hemisphere. The fluctuations in cloud cover and surface temperature engineered by the Antarctic are consequently muted and can be compared with the act of switching on a light fitted with one of these newfangled environmentally conscious, energy saving halogen globes that emit much less light.
Observe that in the last decade surface temperature in the tropics between August and November has fallen away, a departure from the long term trend but not unprecedented.
In the key months where the Arctic has a strong influence on cloud cover and surface temperature (January through to March) a departure from trend manifested a decade earlier in 1997-2006. A cooling trajectory was established in the last decade in all months that are strongly affected by polar atmospheric processes. This is due to a continuing reduction in ozone partial pressure in high latitudes in both hemispheres that goes along with a cooling of the high latitude stratosphere.
We will see that January and February are months of most extreme temperature variability in all latitudes between 30° south and 90° north while June and July are the months when the Antarctic most heavily stamps its authority on temperature between 30°south and 90° south.
We will see that the change in surface pressure due to the flux in ozone in high southern latitudes happens on very long time scales with a swing so wide as to govern the ozone content of the entire stratosphere. The Antarctic makes the centennial swells upon which the Arctic generates the energetic surface chop.
Why did tropical sea surface temperature decline in the decade 1967-76? Why the spectacular increase of 0.5°C over the following two decades? Why the departure from trend between January and March in the last two decades. Obviously, there are more complex factors at work than a the remorseless increase in the very tiny proportion of the well mixed greenhouse gases in the atmosphere.
But let me hasten to add that there is one, naturally occurring greenhouse gas that is quite unequally distributed, that varies in its concentration across the year and over time. It varies under the influence of polar atmospheric processes that dictate the rate of entry of mesospheric air that contains the chief agent of erosion of ozone in the stratosphere described as NOx.
Follow the data, that is what science should be about. If the narrative doesn’t follow the data, its propaganda.
Lets face it, people tell fibs to suit their own purposes.