In general the planet warms as surface pressure increases in low and mid latitudes.
The chain of causation runs like this: Increased surface pressure is associated with increased geopotential height, extra warmth in the atmospheric column and a consequent reduction in the quotient of moisture held in the very expansive ice crystal form. As cloud cover diminishes more solar radiation reaches the surface of the planet. When energy is absorbed by the ocean it is stored to depth and, by virtue of ocean currents, re-distributed, fortuitously warming those parts that receive little solar energy.
In contrast, when solar energy falls on land it is swiftly, in the main overnight, returned to the atmosphere. The warming of the atmosphere that is occasioned in northern summer, due to the extensive land masses of that hemisphere, results in a global deficit of cloud cover in the middle of the year producing the annual maximum in planetary temperature when the Earth is furthest from the sun and solar irradiance 6% diminished by comparison with January. It should be obvious (how did climate scientists miss this?) that the primary dynamic determining surface temperature is the temperature of the atmosphere in relation to the moisture that it contains.
Please inspect the map below. The planetary winds drive ocean currents that mix cold waters from high latitudes and the ocean deep into the warm waters of the tropics. This is evident on the eastern margins of the oceans and particularly so in the southern hemisphere. The Indian Ocean is the odd man out with a weak cold current on its western margins and a warm, southward travelling, current on its eastern margin. The consequence is a relative backwater that is less affected by the mixing of cold with warm water.
It follows that the circulation of the oceans results in a very different thermal regime in each basin according to the the ocean currents that are primarily driven by the winds. As the winds evolve, so do the currents.
The table below documents the extent of the temperature increase over the last 68 years according to latitude and longitude in the three major ocean basins. For economy I focus on those latitudes that are warm enough to be relatively hospitable to man.
It is obvious that the bulk of the Pacific Ocean has not warmed to the same extent as the Indian and Atlantic Oceans. In terms of basin averages, in January the Indian Ocean has warmed by 0.87°C, The Pacific by 0.42°C and the Atlantic by 0.46°C. In July the Indian has warmed by 0.84°C the Pacific by 0.12°C and the Atlantic by 0.6°C. It is in July that the contrast between the oceans is strongest.It is the Indian Ocean that has warmed to the greatest extent.
THE SURFACE PRESSURE DYNAMIC
If we are to understand the differences in the rate of warming of the Ocean basins we need to comprehend to role of polar cyclones in high latitudes. Enhanced polar cyclone activity in the Antarctic circumpolar trough (red and orange in the map above) has, over the period of record, shifted atmospheric mass into low and mid latitudes from latitudes south of the 50° parallel. In consequence the high latitude west wind drift that is coextensive with the circumpolar trough, that drives cold water into the tropics, has accelerated. The flow is restricted at the Drake Passage between the Pacific and the Atlantic. Accordingly the Pacific Ocean cooled in parts and generally warmed at a much reduced rate when compared to the Indian and Atlantic Oceans.
The Indian Ocean is like the canary in the coalmine, a companion to the miner to warn him of a change in the quality of the air. The evolution of surface temperature in the Indian Ocean offers a glimpse of unfettered reality in terms of the march of surface temperature across the globe as it is forced by change in cloud cover associated with shifts in atmospheric mass and the change in the planetary winds.
The remainder of this chapter explores the shift in atmospheric mass from high southern latitudes and its relationship to surface pressure in the rest of the globe and the Indian Ocean in particular.
The discussion is is not based on the hypothetical constructs of a climate model or the abstruse mysteries of so called ‘planetary forcings’. Rather it is grounded in observation and measurement based on data as presented in the reanalysis work of Kalnay et al accessible here.
The graph below represents the evolution of surface pressure in the Indian Ocean south of the equator.We must to answer the question: Why is it so?
The entire southern hemisphere has not warmed in the month of December in the last 68 years. If surface temperature were being forced by increased back radiation from the atmosphere the southern hemisphere should warm in all months. There is no reason to expect the degree of warming due to a hypothetical increase in back radiation to be different in one month to another. We therefore discard the hypothesis that temperature at the surface is driven by the carbon dioxide content of the atmosphere. We look for other mechanisms to explain the flux in surface temperature. Radiation theory is all very well but in the real world, inoperable. The concept of anthropogenic warming is a distraction from fairyland. We can, to advantage, be more discriminating in what we choose to believe.
SURFACE PRESSURE DYNAMICS
Figure 1 compares the evolution of sea level atmospheric pressure in the Antarctic circumpolar trough to all latitudes south of 50° south. It is plain that the relatively short term fluctuations in surface pressure in the larger entity are greater than in the ‘trough’. In point of fact the trough expands and contracts across the parallels affecting surface pressure in adjacent latitudes and in particular across the Antarctic continent. The agent of change is polar cyclone activity that is energised by differences in atmospheric density between very different parcels of air that meet in the region of the trough in the very broad interface between the stratosphere and the troposphere between about 400 hPa and 50 hPa. It is in this region that the strongest winds are to be found. Polar cyclones are generated aloft. This is the nature of the ‘coupling of the troposphere with the stratosphere’, a concept that is a postulate of conventional climate science but remains a mystery so far as its modes of causation is concerned. If one is wedded to radiation theory it limits the mind.
In figure 2 we compare the evolution of surface pressure south of the 50° south parallel of latitude with surface pressure north of that same parallel. If the total mass of the atmosphere were to be invariable we would expect a strictly reciprocal relationship. As pressure falls on one side of the 50th parallel it should rise on the other. Plainly, the increase, decrease and subsequent increase in surface pressure in concert, between 1948 and 1964, is evidence of a planetary evolution in the quantum of atmospheric mass perhaps associated with enhanced loss in very active solar cycles and incremental gain in quiet cycles. That is a subject for another day.
Plainly, since 1964 it is the reciprocal transfer relationship that dominates. When atmospheric mass is lost south of the 50th parallel it moves north the 50th parallel and vice versa.This process of exchange is referred to as the Antarctic Oscillation.
In figure 3 we compare the evolution of surface pressure in the Indian Ocean south of the equator through to 30°of latitude with that north of the 50th parallel.
Figure 4 presents the same information as in figure 3 but on two axes with independent scales. It’s plain that broadly speaking the Indian Ocean south of the equator gains and loses atmospheric mass in parallel with all points north of the 50th south parallel but there are short term differences. These discrepancies are likely due to complex interactions between the southern and the northern hemispheres where, depending on the time of the year the Arctic Oscillation imposes change in the southern hemisphere or in the reverse, the Antarctic Oscillation imposes change on the northern hemisphere, tending to produce ‘mirror image’ results. Short term variations in these two data series can be in opposite directions.
In figure 5 we compare the evolution of sea surface temperature in the Indian Ocean north of the equator with that south of the equator. The data is a twelve month moving average of monthly means so as to remove the seasonal influence. It is plain that the more extreme variations occur north of the equator. Nevertheless the series are very similar in their evolution with generally coincident peaks.
In figure 6 we compare the evolution of sea level pressure in the Indian Ocean to the south of the equator with the evolution of sea surface temperature in the Indian Ocean north of the equator. Sea surface temperature tends to lag surface pressure by a few months. Plainly the Antarctic Oscillation affects sea surface temperature via coincident heating of the atmospheric column as reflected in increased geopotential height driving a reduction in cloud cover.
Figure 7 looks at the relationship between geopotential height and sea surface temperature. Note that geopotential height is strongly related to sea surface temperature but the relationship is not proportional. It is not the increase in sea surface temperature that drives the increase in geopotential height but warming of the air column due to the increase in the ozone content of the air within descending columns of air. These air columns reflect in their temperature the increased surface pressure, the increased warming at the surface and the increase in the ozone content of the descending air. At 200 hPa the air is warmer in winter than in summer due to enhanced ozone content in winter. The temperature of the air is independent of the temperature of the surface over which it lies.
In figure 8 we focus on monthly data. Shown is the departure of a particular month’s data from the whole of period average for that month.
This graph reveals a climate system that is capable of swinging between a sea surface temperature anomaly of about -0.3°C and +1.2°C in an interval of between one and six years. The amplitude of this variation is almost double the increase in temperature that has occurred in the Indian Ocean over the last 68 years. In this circumstance we should simply move on. There is nothing exceptional about this increase in temperature. There is no need to invoke new modes of causation to explain this phenomenon.
Why has surface pressure and sea surface temperature in the Indian Ocean increased almost continuously since 2011? The answer lies in the forces that determine polar cyclone activity in the Antarctic circumpolar trough. Those circumstances relate to the changing nature of the atmosphere in the area of overlap between the stratosphere and the troposphere in high southern latitudes.
As Gordon Dobson observed back in 1925, surface pressure is a by-product of total column ozone. Low pressure cells have more ozone aloft and exhibit a lower tropopause than high pressure cells.
Ultimately polar cyclone activity and surface temperature together with wind direction and intensity and the extent of mixing in the ocean are a function of the ozone content of the air in high latitudes.
The wind goeth toward the south, and turneth about unto the north; it whirleth about continually, and the wind returneth again according to his circuits.
This post revises key concepts that relate to the evolution of climate. Good teaching is about saying it again in slightly different ways until it sinks in. This caters for the students who can’t tune in at a particular time and many others whose perceptual frameworks are sort of ‘frozen’. Its also possible that the message can be delivered without the necessary flair.
Knock-knock. New idea. Fundamental to the nature of Earth is the difference between the warmth of low latitudes and the cold of high latitudes. Without the redistribution of energy by wind and water the extent of the habitable latitudes would be tiny. In the tropics there is little variation in the nature of the air from day to day. But in the mid and high latitudes change is the rule. When the wind changes in a systematic fashion to establish new states, we have climate change. The further we depart from the equator, the greater is the change that is experienced.
The air moves from zones of high to zones of low surface pressure. Pre-eminent in terms of low surface pressure is the Antarctic Circumpolar Trough. It is the zone coloured orange in figure 1.
Kalnay et al’s reanalysis of 1996 to be found here. shows the evolution of surface pressure by latitude over time and is presented in a graphical format in figures 2 and 3.
Plainly, the work that is done in redistributing energy across the latitudes is dependent on the evolution of surface pressure in the Antarctic Circumpolar trough and to a lesser extent the latitudes north of 50-60° north.
Figure 4 plots the temperature of the air as it evolved in the year 2015 at 500 hPa at 40-60° of latitude in the northern hemisphere at left and the southern at right. Plainly there is a north-west to south-east orientation in the movement of the air masses as the atmosphere super-rotates about the Earth in the same direction that the Earth rotates, but faster. The speed of rotation increases in the southern hemisphere where the angle of attack is more aligned with the parallels of latitude. The air spirals from north to south at all latitudes.Warmer parcels will have an ascending tendency while colder parcels will be descending.
THE IMPORTANCE OF POLAR CYCLONES
New Concept: It is polar cyclones that are responsible for the intensity and evolution of the circumpolar trough.
A core theme of this work is that Polar Cyclones are energised by warm, low density cores in that space where the troposphere overlaps with the stratosphere. Differences in the ozone content of the air gives rise to differences in air density. A chain of cyclones on the margins of Antarctica give rise to a rapidly circulating polar vortex in the stratosphere. There are no limits to convection in the stratosphere.
In summer the air rises to the limits of the atmosphere directly over the continent of Antarctica but in winter there is descent. A rising cone of air surrounds the zone of descent. This cone is sometimes described as a polar vortex. The cone begins at 300 hPa over the circumpolar trough and widens to take in the mid latitudes at the highest levels.
The upper troposphere/Lower stratosphere in the region of the circumpolar trough is characterised by intense mixing of air from diverse origins, the troposphere, the stratosphere and the mesosphere.
Between October and March the cone of ascending air below 50 hPa tightens like a hangman’s noose bringing air from the troposphere to the pole, creating an ozone hole, the falling away of surface pressure at this time of the year associated with generalised ascent over the Antarctic continent and so excluding the flow of air from the mesosphere that descends throughout winter.
That the circumpolar trough is due to differences in the ozone content of the upper air should be non-controversial.
THE DENSITY OPACITY OF THE GREEN BLOB
The circumpolar trough is an unremarkable aspect of the atmosphere in the view of UNIPCC. The significance of its presence is unappreciated. This is not an unusual state of affairs in the annals of humanity. In fact, ‘Climate Science’ has not leaned a lot about atmospheric dynamics since the time of the pioneer Bjerknes who published a work on the near surface characteristics of polar cyclones in 1922.
It is realised, at least in meteorological circles, that a trigger is required for the formation of low pressure cells of rotating air in the region of the circumpolar trough. That trigger is an upper level trough, a mass of warmer, low density ozone rich air.
In 1922 it was not apparent that the most vigorous winds are located in the overlap between the stratosphere and the troposphere. Neither was it apparent that cold ozone deficient air from both the mesosphere and the tropical troposphere are drawn towards the circumpolar front in the space shared by the upper troposphere and the lower stratosphere.
In fact the concept of a ‘stratosphere’ was pretty new in 1922. In many respects we have not moved on from that position despite the passage of 100 years. Indeed much that was known prior to the 1970’s has since been forgotten in parallel with the increasing concern that man and the environment in which he lives are incompatible entities. Educators went off in socially responsible directions. A fabulous gravy train was created for scientists and space agencies and all those who aspire to gain their daily bread by looking after the environment, painstakingly monitoring the activities of a an every increasing panoply of despoilers, at one end mighty global corporations and at the other the humble cow that provides the milk for your morning cereal irresponsibly farting in its field of green. Such is the work of the modern missionary.
The intensification of polar cyclones in winter, and the consequent lower surface pressure at that time of the year is due to the proliferation of ozone. Gordon Dobson observed in the 1920’s that, in high and mid latitudes low surface pressure identifies areas with high total column ozone. Dobson measured wind velocity and discovered that the strongest winds were not at the surface but in the region of the tropopause. The tropopause is kilometres lower when surface pressure is low than when surface pressure is high. This circumstance may be described as an upper level ‘trough’, a zone of reduced air density that shows up in elevated geopotential height contours. Had Bjerknes apprehended the structure of the upper air we would not now be worrying about carbon dioxide in the atmosphere. We would be aware that the source of long term climate change, the source of decadal variations, the source of inter-annual variations and indeed our daily weather lies in variations in the ozone content of the stratosphere. We would be at peace with the notion that our ‘rather too cool for comfort’ planet gains and loses energy according to change in the extent of its cloud cover.
According to Mark Twain, when it comes to numbers there are Lies, Damned Lies and Statistics.
Any form of manipulation to achieve simplification involves suppression of information.If one is to draw intelligent conclusions it is better to have all the original data. The less averaging the better.
Even the act of aggregating for a whole hemisphere, as is done in figure 1, is questionable. A sphere exhibits very different characteristics across its surface and so does a half sphere. But, looked at in this way, its better to look at the two hemispheres seperately rather than together. The act of dividing the globe in half at the equator is a reasonable thing to do because the two are very different and we can learn in the process.
In figure 1 we have monthly data. The peak in the cycle is the warmest month and the trough is the coolest month.Between the two are all the other months.
The two hemispheres are about as different as two planets. Temperature in the southern hemisphere (red line) exhibits a smaller annual range. Winter is marginally warmer than in the northern hemisphere. Summer is a lot cooler. In the Southern Hemisphere temperature is moderated by the extensive oceans.
In the Northern Hemisphere temperature is driven up due to the extensive areas of land. This affects high more than low latitudes. The warming of the mid and high latitudes of the northern hemisphere in summer is due to atmospheric heating and loss of cloud cover. More solar radiation gets through the clouds to warm the surface. Paradoxically the Earth is furthest from the sun in July and accordingly solar radiation is 6% weaker by comparison with January. Straight away we see that atmospheric heating and cloud cover is the dominant influence on surface temperature while the degree of variation in surface very much depends on the ratio of sea to land. Who would have thought that? We have been told that it is the ‘greenhouse effect’ that makes surface temperatures what they are. In fact surface temperature depends on whether the Earths natural sunshade is in place or not and just how far a location is from the moderating influence of the sea. There is always less cloud over land than over the sea and particularly in those places where little rain falls.
In fact the ratio of land to water determines the extent of atmospheric warming and cloud cover on all time scales from daily through to annual. This is the strongest influence on surface temperature. Its due to the fact that the temperature of the air changes quickly and to a much greater extent than the amount of water vapour in the air that is required to form cloud. Water vapour content tends to be reduced by cold overnight temperatures giving us dew and cloud in the mornings and relatively clear sky at midday. The closer to the surface of the Earth, the more moisture can enter the atmosphere via evaporation from open water and plant transpiration. The more elevated the location, the colder is the air and , the lower is its moisture content. The higher the elevation, the less the air is affected by warming and cooling at the surface. The higher the elevation the more the temperature of the air is determined by its ozone content.
When the ozone content of air increases and it warms via the interception of long wave radiation from the Earth, the response is measured as increased geopotential height. Surface temperature rises in proportion to geopotential height. That is due to the cloud cover response. Surface pressure, geopotential height and surface temperature all rise and fall together.This is the natural climate change dynamic driven by change in cloud cover.
Enough of these ramblings. Back to figure 1. The dotted lines in figure 1 are strictly horizontal. They have no slope. These lines assist the eye to detect variations. There is a relatively small variability in temperature in the southern hemisphere in summer (upper limit of red series) over the last 69 years and no obvious trend. On this basis one can rule out carbon dioxide as a driver of surface temperature because the gas is well mixed. If there is a back radiation effect it needs to show its face here. Palpably it doesn’t. If the back radiation effect depends at all on enhancement by humid air and the presence of cloud we should see a continuous increase in the temperature of the air in the southern hemisphere from November through to March because this is the time of the year when cloud cover peaks. But, we see that there is no change in surface temperature in the warmest month of the year. However, we do see a gradual increase in coolest month temperature in the southern hemisphere from about 1970. This is the warming that needs to be explained.
Now, lets look at the northern hemisphere. Coolest month temperatures rise and fall over quite short time intervals. The 1970’s are the coolest decade in the northern hemisphere in terms of both the warmest summer month and the coolest winter month. Northern Hemisphere temperature increased after 1998 in both coolest and warmest month and this too needs to be explained.
A QUESTION OF TIMING
The raw data doesn’t inform us as to whether the climate cooled or warmed in spring or autumn. Does that matter? Come to think of it, if the global average rises due to an increase in temperature in the winter months is that really a problem. Would we not actually prefer warmer winters? Can we make rational decisions on the basis of a global average? Not really! Under a regime of dramatically increased summer temperatures with thousands dying of heat stroke and and dramatically reduced winter temperatures with thousands freezing to death, the average may be unchanged. We may think the planet is warming if we see a rising global average. But that could simply represent some warming in the coldest, abominably cold month so that month is slightly less abominably cold. Quoting the global average is the sort of thing that Mark Twain was complaining about.
Having dispensed with the CO2 furphy and the global average furphy we can now concentrate our on why the temperature changes as it does!
WHY HAS SURFACE TEMPERATURE CHANGED AS IT HAS
What stands out most in figure 1 is the warming that occurs in the southern hemisphere in winter (red line) starting in the 197o’s.
Given that the temperature of the air is a chilly 11°C in mid winter, this warming, and even more so, the warming of the northern hemisphere in winter, is unequivocally beneficial. This is a matter for congratulation rather than concern. We live in fortunate times. But it would be nice to know why this is happening because winter warming inflates the average for the globe as the whole and gives rise to a lot of hysterical nonsense that is swallowed by an uncritical media that take the point of view that the science of climate is a matter for ‘scientists’ and the average global temperature is Gods Word. These people have no idea what Mark Twain was talking about.
Politicians don’t read science. They read the daily papers. We get the blind leading the blind and a cabal of irresponsible scare mongers beating the drum and clashing the cymbals while snapping at the politicians heels demanding ‘clean energy’ and an end to ‘carbon pollution’. This is the modern ‘left’ in action. Its the Democratic Party in the US, the moneyed elite in the UK and an unholy alliance of Labour, The Greens and the soft underbelly of the Liberals in Australia. Even the Chinese, who in many ways are very practical people, seem to have fallen in love with this idea. If you muzzle the press, put the intellectuals in prison and rule with an iron fist you can do whatever you bloody well like. Can we pretend that what is happening in the West is somehow preferable? Can we point to a more rational and beneficial result from our ‘democratic process’? Cast not the first stone.
A PLAUSIBLE EXPLANATION
The warming of the northern hemisphere in both winter and summer starts in about 1998. Bear in mind that the warming in southern winter occurs at a time when global cloud cover plummets as the large land surfaces of the northern hemisphere heat the atmosphere. Is that warming due to an increasing ozone content of the air and a consequent decline in cloud cover?
Figure 2 confirms a step up in temperature at the 10 hPa pressure level after 1976. This is predominantly a southern hemisphere phenomenon. The step up occurs in winter.The consequent much enhanced feed of ozone into the high pressure zones of descending air over the global oceans would reduce cloud cover. Under normal circumstances 90% of global cloud cover is to be found over the oceans and this is where high pressure cells form, especially in summer. When ozone rich air descends in a high pressure cell, the air warms (geopotential height increases) and this is always, without exception, associated with warming at the surface.So, the warming is due to loss of cloud cover.
Now, I want you to sanction something quite unorthodox and shocking.
In figure 2 the hand drawn line that links the high points in the summer maximum in the northern hemisphere is copied and applied to the northern minimum and to both the minimum and the maximum in the southern hemisphere. This unsophisticated ‘sleight of hand’ is performed as a ‘seeing aid’ to discern the points of difference. I guess I am just a frustrated artist and the mathematical exactitude of Excel is humanised by this process.I was once told by a plant breeder that if you cannot see the difference in plant performance by eye that difference is not worth measuring. It’s somehow comforting to realise that we don’t always need mathematical manipulations in order to get to the nub of the question.
Some points to note:
Winter minimums are more variable than summer maximums and particularly so in the northern hemisphere.
At the surface, the widest range in temperature between summer and winter is seen in the northern hemisphere but that is not the case at 10 hPa. It is the southern hemisphere that exhibits the big variations.
Now in the last point we have an anachronism and a clue. See Figure 3.
The wide range in temperature at 10 hPa in the southern hemisphere is due to the variable intake of mesospheric air over Antarctica in winter. This intake of cold air cools the upper stratosphere. It does not affect the temperature of the air at elevations below 300 hPa. The deepest cooling occurs at the 30 hPa pressure level in July. Why is it so?
In winter surface pressure in the Antarctic region reaches a resounding planetary high. Nowhere else, anywhere on the globe, in any season of the year does surface pressure approach that achieved over Antarctica in winter. Air from the mesosphere has a low ozone content and it dilutes the ozone content of the atmosphere generally.The enhanced flow of mesospheric air into the southern hemisphere causes a generalised deficit in the ozone content of the air in the entire southern hemisphere. Alternatively, when the flow is choked off (surface pressure rises) there is an increase in the temperature of the air and its ozone content.
It is easy to see how the ozone content of the air can change over time via an alteration in the mesospheric flow.
See figure 4 below. The short term variability that is seen in Arctic is much enhanced after February. It is initiated by a fall in polar surface pressure signalled by a rise in the Arctic Oscillation Index (the two are inversely related). This increase in 10 hPa temperature is likely reinforced in amplitude and duration by an increase in ozone partial pressure due to enhanced penetration of ionising cosmic rays as the stratosphere warms. The build up in the temperature over the polar cap is avalanche like in its suddenness. It represents the displacement of cold mesospheric air. The heating effect, observed to last for weeks at a time, requires amplification to persist in this way. Otherwise it would be gone in ten days. Without amplification the descent of mesospheric air should re-establish in short order . Patently it does not.
Figure 4. Mean temperature at 10 hPa compared with the Arctic Oscillation Index.
In Fig. 2 we observe little difference between the hemispheres in the evolution of 10 hPa temperature in summer. There is a slight step up in 1976. And, the step up in summer is greater in the south than the north.The change in the ozone content of the atmosphere is global, affecting the entire year and it is related to a fundamental change in the atmospheric circumstances over Antarctica, most pronounced in the winter season.
The ozone content of the air is rapidly propagated across the globe as we will see in figures 6 and 7 below. This testifies to the strength of horizontal winds in the stratosphere and most particularly in the area of overlap where stratosphere and troposphere occupy common ground.
So, the standout anomaly in figure 2 is the step change in 10 hPa temperature in southern winter after 1976. This step change in 10 hPa temperature is reflected in surface pressure data in figure 5 below.
In fact this step change in 1976 is reflected surface temperature data at every latitude across the entire globe as documented here.
THE ACTIVE INGREDIENT:OZONE
As Gordon Dobson discovered in the 1920’s surface pressure is a reflection of the ozone content of the air and vice versa. The fall in surface pressure at 75-90° south latitude documented in figure 5 is a direct consequence of the increase of the ozone content of the air. It is the ozone content of the air that affects its density, the weight of the entire column and hence surface pressure.
Wind strength in the atmosphere is intimately connected with the ozone content of the air. The air is relatively still near the surface of the planet and also at the highest elevations. Wind velocity is most enhanced in the overlap between the stratosphere and the troposphere between 300 hPa and 50 hPa where abrupt change in the height of the tropopause is associated with jet streams.
The 10 hPa level is virtually the top of the atmosphere because 99% of atmospheric mass is below that pressure level. The rapidly ascending circulation at the pole elevates ozone producing the greatest temperature response at the highest elevations as is evident in Fig 6. The strong temperature response at 10 hPa is due to convection of ozone rich air that increases ozone partial pressure at the highest elevations. That ozone mixes across the profile and affects the ozone content of the air in descending circulations in mid and low latitudes.
The pressure gradient (density differential) across the vortex in the upper troposphere/lower stratosphere where polar cyclones are initiated determines the strength of convection. The density differential is increased seasonally as the ozone hole is established below 50 hPa when NOx rich air from the upper troposphere is drawn into the circulation over the polar cap during the final warming of the stratosphere.
The incidence of very much higher temperature at the 10 hPa pressure level after 1978 represents a step change in the fundamental parameters of the climate system. There is not one climate system here but many, as many as there are days in the year. Changing the ozone content of the air in high latitudes alters surface pressure differentials and therefore it changes the planetary winds.
A QUESTION OF TIMING
In figure 7 below we chart the evolution of 10 hPa temperature in selected months from the mid latitudes to the southern pole.
10 hPa temperature over the pole is greater at 80-90° latitude than at lower latitudes in summer. This is when mesospheric air is excluded and ozone rich air gently ascends to the top of the atmosphere. This phenomenon occurs over Antarctica between October and February.
10 hPa temperature over the southern pole is inferior to that at lower latitudes when mesospheric air is drawn into the circulation between March and October.
After 1978 we see a change in the temperature profile in all months. This is particularly so from June through to November. The transition month for the final warming prior to 1978 was November. After 1978 the transition occurs in October. Taken all-together this data indicates a fundamental change in atmospheric dynamics that inevitably produces an increase in surface pressure, geopotential height and surface temperature in mid and low latitudes.
This is the source of the warming in southern winter. It has nothing to do with the works of man.
The change in the temperature of the air at the 10 hPa pressure surface in the Arctic is a product of the combined influence of atmospheric dynamics at both poles. The Arctic is independently influential. Its calling card is extreme temperature variability in January and February. This can be seen in Figure 1 in the surface temperature in the coolest months.
Climate change is a matter of observation and common sense. There is not much of it about. When it comes to numbers there are Lies, Damned Lies and Statistics. Undoubtedly the leading offender is the global average of surface temperature as disseminated by GISS, The NOAA and the Hadley Centre, all dedicated to the dissemination of information in support of the nefarious activities of Global Green and the UNIPCC.
In this post I give an account of the data provided in two papers from a group of authors who have described the the nature of the atmosphere and its dynamics in terms of its ozone content. The work creates a framework that advances our understanding of atmospheric processes and how they relate to external influences in an open system. In introducing the papers I provide an interpretation of atmospheric dynamics that goes beyond that of the authors and it will be best if readers go direct to the originals as a preliminary activity before reading what follows.
The Total Ozone Field Separated into Meteorological Regimes. Part I: Defining the Regimes ROBERT D. HUDSON, ALEXANDER D. FROLOV, MARCOS F. ANDRADE, AND MELANIE B. FOLLETTE Published in 2003 and accessed here.
Traditionally, studies in the stratosphere using column ozone amount, ozone profiles, and dynamical variables at midlatitudes have centered on zonal averages of these quantities made over specific latitude bands. This is in sharp contrast to the studies made within the polar vortices where the average is made within regions defined by potential vorticity, a meteorological parameter. An analysis of the ozone field in the Northern Hemisphere outside of the polar vortex is presented in which it is shown that this field can also be separated into meteorological regimes. These regimes are defined as 1) the tropical regime, between the equator and the subtropical front; 2) the midlatitude regime, between the subtropical and polar fronts; 3) the polar regime, between the polar front and the polar vortex; and 4) the arctic regime, within the polar vortex. Within each regime the zonal daily mean total ozone value is relatively constant, with a clearly separate value for each regime. At the same time, the stratospheric ozone profiles are clearly distinguishable between regimes, each regime having a unique tropopause height. A midlatitude zonal average, whether of ozone profiles, total ozone, or dynamical variables, will depend on the relative mix of the respective values within each regime over the latitude range of the average. Because each regime has its own distinctive characteristic, these averages may not have physical significance.
Here is the introduction to the work:
Dobson et al. (1927) reported ground-based measurements of the total column ozone using a spectrometer that observed the solar ultraviolet irradiance. They noted that when an upper-tropospheric front passed over the instrument, the total ozone value either dropped or rose sharply. Shalamyanskiy and Romanshkina (1980) and later Karol et al. (1987) divided ground-based total ozone measurements into three regions, separated by the polar and subtropical jet streams. They found that total ozone and temperature profiles had small variability within each region but changed sharply at the polar and subtropical fronts. The same change in ozone across a frontal boundary can be seen in the data from the Total Ozone Mapping Spectrometer (TOMS; McPeters et al. 1996).
Now, the authors don’t go on to say that the jet streams at the fronts are a product of a contrast in air density in part due to the heating activity of ozone. They must give due respect to the school of climate science that sees the Earth as a closed system. If they took account of their own observation that, when moving from equator to Pole, the tropopause steps down in elevation at the subtropical front and again at the polar front where, on the polar side of the front there is no tropopause at all, thereby giving rise to severe gradients in atmospheric density then perhaps they might hypothesise that ozone is THE critical factor giving rise to jet streams, determining the weather patterns in the troposphere and the evolution of climate over time. But we must bear in mind that the climate establishment would punish them if they ventured that viewpoint. It is safer to leave the question open to interpretation. Those who would maintain that the distribution of ozone is a product of atmospheric dynamics in the lower troposphere and the chlorine content of the polar atmosphere due to the escape of chlorofluorocarbons into the atmosphere from refrigerants etc etc, can then interpret matters as they prefer.
In establishment climate science there is no concept of ozone variation on an inter annual basis due to the activity of the mesospheric vortex at the pole or ozone production due to cosmic radiation. The atmosphere is not an electromagnetic medium capable of change in its rate of rotation due to change in the solar wind. In the conventional viewpoint the temperature of the stratosphere is not driven by the absorption of long wave radiation from the Earth by ozone but by the interception of short wave radiation from the sun. In other words the direct impact of short wave radiation from the sun as held to be the reason for the temperature of the stratosphere even on the night side and regardless of latitude. The planetary winds are held to be driven according to the energy absorbed in near equatorial latitudes. Adherents don’t know how the atmosphere is shifted from high latitudes to low latitudes and wont be drawn to speculate on that matter at all. The blinkers are very firmly in place. Grant money and ones livelihood is at stake. Privately, one may admit in a whisper, that the Emperor has no clothes but publicly he is beautifully arrayed in the most impressive garments that money can buy.
In spite of these niceties some very useful analytical work has been done that establishes the distribution of ozone in relation to the position of the subtropical and polar fronts and there are big surprises that have very important implications in furthering our understanding of atmospheric dynamics..
In terms of atmospheric dynamics in the northern hemisphere we can note that the situation is different to that in the southern hemisphere. The circumpolar trough in surface atmospheric pressure surrounding Antarctica is so deep, and persistent across all seasons as to act as a global sink, conditioning the movement of the atmosphere globally. By contrast, in the northern hemisphere a trough of sorts develops in the north Pacific in winter associated with regional ascent of ozone rich air to the top of the atmospheric column while high surface pressure that is associated with the Antarctic continent in winter is associated with the Eurasian continent during winter, in the same latitude as the North Pacific low pressure zone.
It should be emphasised at the outset that the data in this study relates to a single day, the 11th March 1990. I will explore the importance of this choice by way of a postscript. In now way is the legitimacy or the conclusions of this study adversely affected by the fact that the data represents a single day. In fact, it is only by concentrating ones effort on single day that one can discern the dynamics at work.
Of immediate interest is that the stretched Mercator’s projection of Fig 1 involves spatial distortion. The fingers of low ozone content air interlaced with fingers of high ozone content air would look different in a polar stereo-graphic view and they are strictly an artefact of the circulation on a particular day. The configuration of the northern hemisphere circulation is complex and ever changing due to the distribution of land and sea. If we were looking at the very much simpler circulation in the southern hemisphere it would be immediately apparent that air of tropical origin is drawn into a super-rotating west to east circulation with its highest rate of rotation at the polar vortex. The vortex is a feature of the stratosphere linked to an ascending circulation via a chain of polar cyclones that entrain air from the troposphere, air from the stratosphere and air from the polar cap that has descended from the mesosphere. The vorticity of these polar cyclones and the stratospheric vortex depends upon contrasts in air density between one side of the vortex and the other.Note the location of the blue area (high ozone) and the green area (low ozone) in relation to the vortex. The authors locate the vortex in this way: “The solid red line marks the position of the sharp gradient in the isentropic potential vorticity (IPV) contours on the 450- K isentropic surface, which traditionally is assumed to mark the edge of the polar vortex”.
The 450-K isentropic surface lies between 70 mb and 50 mb pressure surfaces. This is at the altitude where ozone is in greatest abundance in the vertical profile. It is unequivocally in the stratosphere. It will therefore be the location where the ozone density gradient is steeper than anywhere else in the vertical profile giving rise to very strong winds. Notice that there are two gaps in the the blue-black zone of highest ozone content These are areas of downdraught of low ozone content mesospheric air associated with the high pressure cells over land. One lies over East Asia and the other in the vicinity of Iceland. It is no accident that the vortex follows the junction of high ozone content warm air to the south and low ozone content cold air to the north. Unequivocally, elevated vorticity is linked to differences in air density linked to the origin of the air, its trace gas content, including ozone and NOx (not shown but always present in air from the troposphere), the formation of polar cyclones and therefore the flux in surface pressure between high latitudes and elsewhere that varies on all time scales. This flux in the pressure differential between high and mid latitudes is measured as the Arctic Oscillation and the Antarctic Oscillation.
What is described as the polar front in this work is likely a near surface phenomenon, the outer interface of a chain of polar cyclones that feed air into the Polar Vortex. The zone between the polar font and the polar vortex has very high ozone values. It is a zone of intense convection that is generated at the elevation of the Polar Vortex, propagating down to the surface where its troposphere manifestation is called a ‘cold core’ polar cyclone. No cyclone can develop with a cold core. The warm core is aloft where ozone captures outgoing radiation from the Earth.
TRANSITIONS AND UNEXPECTED HOMOGENEITY
Hudson et al notes in respect of the ozone data: The average for all of the data slowly increases with latitude until the polar vortex is reached. On the other hand, the average for the tropical, mid latitude, and polar regimes is relatively constant over a wide range of overlapping latitudes. There is also a clear difference between the average total ozone amounts for each of these regimes.
The transition zone between these dissimilar regions is referred to as a ‘front’. The Polar Front only exists in the winter months when mesospheric air descends to jet stream altitudes its rate of flow and integration with the wider atmosphere contributing to the flux in the ozone content of the atmosphere generally. But this is not a dynamic that is mentioned in this work. In summer there is no descent of mesospheric air and its disappearance is described as the final warming of the stratosphere after which the air over the polar cap gently ascends. In summer a high ozone values over the Arctic Ocean contribute to generalised ascent and the jet stream structures are fragmented.
Hudson et al reports that the fronts between different ozone regimes exhibit the same ozone content around the entire globe at any particular time. However the values are different according to the month of the year.See figure 3 below: In winter the fronts have higher ozone values than in summer. This emphasises the basic cell like structure and the homogeneity found within cells.
At the polar front the ozone value is highest in February. Readers of earlier chapters in this work will know that surface temperature variability between 30° south and 90° north latitude is greatest in January and February. There is a causal connection. The year to year variability in ozone partial pressure at the polar front is greatest in winter when ozone partial pressure is highest. In the transition from autumn to winter surface pressure over the Arctic rises strongly in November as the Antarctic releases atmospheric mass as the final warming in the stratosphere takes place. The increase in mass in the Arctic in November is reflected in the Arctic Oscillation Index (low values). In December, as ozone builds giving rise to active polar cyclones, surface pressure in high latitudes falls just as strongly as it has risen in the transition from autumn to winter. In this way, as Gordon Dobson observed, surface pressure is linked to the ozone content of the air. More importantly, as surface pressure falls in the Arctic a warm wind from the south finds its way further north bringing clement conditions. The zone of Ascent in the North Pacific develops strongly taking ozone to the top of the column. The return circulation brings ozone into the high pressure cells of the mid latitudes, warming the air, increasing geopotential height, reducing cloud cover and increasing surface temperature.
These points are worth repeating. Gordon Dobson pointed out that ozone maps surface pressure with high ozone values corresponding to low surface pressure. Low pressure in the Arctic brings a flood of warm air from the south. Cool air is replaced by warm air. This is the Arctic Oscillation in action. In more recent terminology the AO is called the ‘Northern Annular mode’. It is not in the interest of the authors of this study to link ozone dynamics to change in surface temperature wrought by a change in the origin of the air. The notion that surface temperature is a response to the presence of carbon dioxide in the atmosphere has to be maintained if ones work is to appear in academic journals like ‘Science’ although the newly appointed editor of Science is reported to be saying that ‘science’ has lost integrity in the process of suppressing competing viewpoints. See here where it is reported that: “Science editor-in-chief sounds alarm over falling public trust. Jeremy Berg warns scientists are straying into policy commentator roles.” Are the publishers of ‘Science’ reacting to falling circulation related to negative reader response? If so, this will be good for small ‘s’ science.
EVOLUTION OF OZONE PARTIAL PRESSURE AT THE FRONTS
It is very interesting that the authors report that the ozone content of the air in the ‘Midlatitude Regime’ is invariable around the globe regardless of latitude or longitude. Apparently atmospheric mixing processes maintain this homogeneous state. This reinforces the long held view of a cellular structure in the atmosphere between the fronts. Inferentially, it supports the notion that elevated ozone in the ‘Midlatitude Regime’ is a product of in-situ ionisation of the polar atmosphere by cosmic rays during the polar night rather than transport from the tropics where the ozone content of the air is inferior. If one conceives the situation in this way it is obvious that the ozone content of the air in high and mid latitudes is driven by forces that are external to the system via polar dynamics rather than the interaction of short wave radiation with the atmosphere. The stratosphere warms in the winter hemisphere in the mid latitudes, obviously unrelated to the incidence of short wave radiation. This accentuates density differences across the fronts driving enhanced vorticity. External forces are capable of mediating the strength of the zonal wind in an electromagnetic medium such as the atmosphere, mediating the penetration of mesospheric air and the penetration of cosmic rays that very much depends on air temperature and density. Due to ionisation by cosmic rays it is possible for the synthesis of ozone to occur in the absence of short wave solar radiation.
EXTREME OZONE GRADIENTS, TROPOPAUSE STEPS, JET STREAMS ARE ALL LOCATED AT THE FRONTS
Hudson notes that using aircraft to measure ozone partial pressure both Shapiro et al. (1987), and Uccellini et al. (1985), found a strong coincidence between large gradients in the total ozone measurements from TOMS and the position of upper-level jet streams, the frontal zones and tropopause ‘foldings’ where there is a step up in the height of the tropopause.
Note the difference in the height of the tropopause across the three regimes for North America.on 11th March with Tropical (250 hPa), Midlatitude (300hPa) and Polar (400 hPa) The fronts between these regimes consequently exhibit steps. At these steps marked differences in air temperature and density manifest in the horizontal plane. This is an unstable situation. From figure 4 (Hudsons Fig 9) we see that in the tropical regime, the temperature of the air at the tropopause is -70°C, in the Midlatitude zone it is-60°C and in the Polar regime -50°C. In this circumstance, at the vortex, because temperature reflects density, the vertical interval between 400 hPa and 300 hPa, a distance of some 2 kilometres will be marked by continuous upwards displacement of low density air and as a result this displaced air will circulate about the globe as an ascending jet on the margins of the tongue of cold dense mesospheric air with occasional discontinuities (as noted above in relation to east Asia and Greenland) that will be marked by extreme turbulence. As this air ascends it must be replaced from below drawing in ozone rich, low density air from lower latitudes together with NOx rich air from the troposphere and some air from the region of the polar cap that is derived from the mesosphere via subsidence.
WHERE DOES THE ENERGY COME FROM TO DRIVE THIS SYSTEM
The energy is supplied via the Earth itself in the form of infrared radiation at twenty times the wave length of the energy originally derived from the sun. The agency for its transmission to the atmosphere is ozone that imparts energy with an efficiency that varies directly with surface pressure. It is here, at the polar vortex that the system exhibits the river of energy thus acquired, not in the tropics where the air is quiescent. The ascent does not respect a ‘tropopause’ because it goes to the top of the atmosphere giving rise to localised ozone ‘hot spots’ at 1 hPa. These hot spots are likely found over the warmest part of the oceans in mid to high latitudes. When inspecting the temperature response in the upper stratosphere we see that temperature volatility increases with altitude, particularly above 30 hPa.
The system continuously elevates ozone to the top of the atmosphere from where it must return within the Midlatitude cell. If there is appreciable loss of ozone via ionisation or chemical erosion in the upper upper levels of the Midlatitude cell there must be sufficient ozone created to remedy the loss and so provide the means to energise the system on a continuous basis, day and night. The Earth obliges in terms of the energy requirement. But where does the ozone come from to replace that lost to chemical depletion and destruction by short wave energy from the sun?
A seasonal low in the incidence of short wave radiation from the sun means that the ozone necessary to sustain this system is not available from the solar source in the winter hemisphere. It’s unlikely that the requisite ozone could be sourced from the subtropical zone in the summer hemisphere that is remote, across the equator where in any case ozone partial pressure is quite low and always so. So much for the Brewer Dobson Hypothesis! There is however another source of ionisation via cosmic rays.
The waxing and waning of the polar jet stream will reflect atmospheric dynamics due to the changing ozone content of the air, inducing changes in density gradients across the polar front that in turn affects the rate of intake of mesospheric air. Ionisation by cosmic rays depends upon air temperature almost certainly generating an ozone production dynamic that will amplify change according to the activity of the sun. These interactions affect vortex and polar cyclone activity that vary from week to week, year to year and across the decades according to the incidence of solar activity. Note the incidence of stratospheric ‘warmings’ in figure 5 from January through to April during which the muon count from cosmic ray activity, as measured at the surface and in ice cores is known to respond directly to the changing temperature of the stratosphere. The muon count is a direct proxy for the incidence of cosmic rays and indirectly a proxy for solar activity. See here for background or here for a lecture presentation.
INCIDENCE OF CHANGE IN THE CHARACTER OF THE AIR BETWEEN 400 HPA AND 40 HPA.
From figure 6 (Hudson 10) we can infer that the degree of variability in the source and ozone content of the air in the upper troposphere/lower stratosphere increases from the equator to the pole and is most marked in the polar regime that only manifests in winter. We see that the largest variations in ozone partial pressure in the North American polar regime manifest between 400 hPa and 40 hPa. This interval carries 36% of the mass of the atmospheric column. Because ozone maps surface pressure and it produces the lowest surface pressures in high latitudes this guarantees that the atmosphere must move from the equator towards the poles. Om the southern hemisphere this movement occurs in a gentle spiral with the air coming from west north west to east south east. Such is the strength of the Antarctic circumpolar vortex that the direction of movement is the same in the northern hemisphere. The vertical intervals where this movement is strongest can be inferred from fig 6. The region between 400 hPa and 40 hPa encompasses the upper troposphere and the lower stratosphere. That this region sees the greatest mobility has implications for the ozone content of the air over the polar cap when the final warming of the stratosphere occurs and mesospheric air is replaced by troposphere air rich in NOx giving rise to an ‘ozone hole’ and so ending the period where the Polar Front is in existence. This circumstance was not appreciated at the time when environmental activists succeeded in having many nations subscribe to the Montreal Protocol to limit emissions of certain halogens supposedly responsible for the ozone deficit. The dynamics behind the creation of the celebrated Ozone Hole are a mystery to climate science to this day.
ORIGIN OF THE DRIVER OF THE GLOBAL CIRCULATION
The surface pressure differential between low and high latitudes directly governs the circulation of the air near the surface and to first order determines the equator to pole temperature gradient. In addition, minor change in the ozone content of the air in the tropical and mid latitudes will drive change in geopotential height at all elevations and with it cloud cover and surface temperature. It should be born in mind that the circulation of the air at the 10 hPa level is equator-wards rather than pole-wards. Accordingly, ozone descends from the top of the atmosphere in mid and low latitudes within high pressure cells.Apart from the surface temperature effect due to change in the origin of the surface winds, the variability in the ozone content of the air in mid and low latitudes drives a change in cloud cover to further amplify the temperature effect due to the change in the origin of the wind. These are the central dynamics behind climate change on week to week through to inter-centennial time scales. Surface temperature varies directly with surface pressure and geopotential height. This is the nature of climate change.
The natural variation in sea surface temperature in the southern hemisphere is seen in Figure 7. In terms of causation that figure is instructive.
Climate change in the southern hemisphere, considered as an entity, measured in terms of sea surface temperature, is largely a matter of temperature change in the winter months. The hemisphere is no warmer in December in the latest decade than it was seven decades ago. An inference as to the origins of climate change is not hard to draw. There is no room here to infer an anthropogenic effect via back radiation.
The relationship between the ozone content of the air and its temperature is provided in figure 8 ( Hudson 11). The lack of a 1/1 correspondence between the ozone content of the air and its temperature, given that ozone is an absorber of long wave radiation from the Earth and that this activity is the primarily cause for the unexpected warmth of the stratosphere, is due to the marked flux in the direction of the movement of the air in the stratosphere with warmer air of polar origin that has a lower temperature but a higher ozone content tending to move towards the equator above the 50 hPa pressure level while cold ozone deficient air from the mid latitudes and the tropics moves pole-wards between the 400 hPa and 40 hPa pressure levels. The latter produces tongues of cold, relatively ozone deficient air showing up in daily and weekly data but obliterated in averaged data over longer time intervals. This phenomenon is reflected in figure 10 as a higher standard deviation in the partial pressure of ozone between 400 hPa and 40 hPa in the mid latitude and polar regimes. This marked variability due to the origin of the air finds its ultimate expression in the Antarctic ozone hole that manifests below 50 hPa at the time of the final warming of the upper air in spring. Its absence in the northern hemisphere is due to the configuration of land and sea.
The acute reader will realise that there is no room in this circulatory regime for the Brewer Dobson hypothesis generated in the 1950’s as a possible explanation for the elevated ozone content of the air in high latitudes. The air below 40 hPa moves in the direction of Antarctica or to the Arctic and is generally ozone deficient. The air above 40 hPa comprising just 4% of the atmospheric mass, moves equator-wards and as it does so is increasingly subject to ionisation of ozone by ultraviolet B from the sun.
THE FLUX IN OZONE ACROSS THE SEASONS
Mean total ozone in Dobson units exhibits a different pattern of seasonality in each regime as seen in Fig 9, (Hudson’s figure 13).
Variability in total ozone in the tropics peaks in January and February with a subsidiary volatility emanating from the Antarctic from August through to December that is associated with final warming dynamics.
Mid latitude and tropical regimes in both hemispheres exhibit strong variability in northern winter driven from the Arctic. This translates directly to variability in surface temperature. This is natural climate change in action driven by the ozone content of the air in the upper troposphere and lower stratosphere. As noted above it operates by changing the origin of the wind and the extent of the Earths natural umbrella, cloud cover that on average shields 70% of the surface of the earth, less in northern summer and more in northern winter. Accordingly the greater amount of cloud is present when the Earth is closest to the sun in January and the greatest variability in surface temperature across the most of the surface of the earth including the all important southern oceans also occurs in that month. It is no accident that the Pacific Ocean tends to exhibit its largest swings in temperature in January and that marked variability in surface temperature in January can be discerned in temperature data even in high southern latitudes.
The Arctic Polar regime shows a strong maximum and peak standard deviation in the middle of winter but also a marked amount of variability driven from Antarctica in northern autumn / southern spring at the time when surface pressure falls to its annual minimum at 60-70° south latitude. This is where polar cyclones are generated on the margins of Antarctica and is the location of the absolutely dominant southern vortex..
CHANGE OVER TIME AND THE MANNER OF CHANGE
There is a second paper from these authors to be found here.:
The total ozone field separated into meteorological regimes – Part II: Northern Hemisphere mid-latitude total ozone trends R. D. Hudson1 , M. F. Andrade2 , M. B. Follette1 , and A. D. Frolov3 Published 2006.
Previous studies have presented clear evidence that the Northern Hemisphere total ozone field can be separated into distinct regimes (tropical, midlatitude, polar, and arctic) the boundaries of which are associated with the subtropical and polar upper troposphere fronts, and in the winter, the polar vortex. This paper presents a study of total ozone variability within these regimes, from 1979–2003, using data from the TOMS instruments. The change in ozone within each regime for the period January 1979–May 1991, a period of rapid total ozone change, was studied in detail. Previous studies had observed a zonal linear trend of −3.15% per decade for the latitude band 25°–60° N. When the ozone field is separated by regime, linear trends of −1.4%, 2.3%, and 3.0%, per decade for the tropical, midlatitude, and polar regimes, respectively, are observed. The changes in the relative areas of the regimes were also derived from the ozone data. The relative area of the polar regime decreased by about 20%; the tropical regime increased by about 10% over this period. No significant change was detected for the midlatitude regime. From the trends in the relative area and total ozone it is deduced that 35% of the trend between 25◦ and 60◦ N, from January 1979–May 1991 is due to movement of the upper troposphere fronts. The changes in the relative areas can be associated with a change in the mean latitude of the subtropical and polar fronts within the latitude interval 25◦ to 60◦ N. Over the period from January 1979 to May 1991, both fronts moved northward by 1.1±0.2 degrees per decade. Over the entire period of the study, 1979–2003, the subtropical front moved northward at a rate of 1.1±0.1 degrees per decade, while the polar front moved by 0.5±0.1 degrees per decade.
The subtropical and polar fronts are associated with the subtropical and polar jet streams, and have mean latitudes of about 30° and 60° N, respectively
The positions of the subtropical and polar fronts defined in Hudson et al. (2003) vary on a daily basis as the Rossby waves meander about their mean latitudes. These fronts are not be confused with the cold and warm fronts associated with cyclonic flow close to the surface.
Note that: When the ozone field is separated by regime, linear trends of −1.4%, 2.3%, and 3.0%, per decade for the tropical, midlatitude, and polar regimes, respectively, are observed. It is not possible that a linear trend of 3% per decade could be driven from the tropical regime where the trend is -1.4% per decade. To achieve this disparity the ozone trend has to be independently created in high latitudes, and likely more from one pole than the other. It is in fact the Antarctic that drives the multi-decadal and inter-centennial trend.
The authors note that: Between January 1979 and May 1991, the relative area of the Polar regime decreased by about 20%, while that of the Tropical regime increased by about 10%. There was no significant change in the relative area of the Midlatitude regime over this time period. These changes imply a net poleward movement of the subtropical and polar upper-troposphere fronts. That in itself warms the surface.
The fronts define the extent of the hemisphere occupied by masses of air of different temperature. If the northern hemsiphere fronts move north the hemisphere warms. The northward migration of the subtropical front implies an expansion of the relatively cloud free area and an increase in the energy absorbed by the oceans.
In this way, change in the ozone content of the air brings about a change in the surface temperature and the energy circulating within the Earth system. When one looks at the data as seen here, this mode of change is entirely consistent with the pattern of temperature change observed between 1948 and the present time.
The manner in which the top down generation of surface weather occurs, from stratosphere to troposphere, has been a matter of debate for almost twenty years in connection with what has been described as the ‘annular mode phenomenon’. The papers reviewed in this post are amongst the more significant works published in the field of climate science since the work of Gordon Dobson who devoted his life to the measurement of total column ozone. If we are to be critical, the shortcoming lies in failing to look at the historical record over a longer time interval, to examine the situation in the southern hemisphere and to speculate about mechanisms responsible for change. Simple questions like ‘Why is it so? and ‘What does this mean for the evolution of surface temperature?’ are of the greatest importance but it is precisely in this area that the politics of climate change get in the way. Accordingly, the link between ozone and the formation of polar cyclones that relates to the evolution of surface pressure in high latitudes is not made. Nevertheless these papers ably support the most cogent explanation of the manner in which natural variations in weather and climate can occur on week to week through to centennial time scales.
Unfortunately, climate scientists are off with the fairies with their CO2 forcing hypothesis and show no sign of a desire to research the manner in which the climate of the Earth responds to external influences. Work that suggests that the climate system is subject to external forcing is simply ignored… much to the detriment of humanity.
Variability in the distribution of ozone is a feature of the northern hemisphere as the following diagrams reveal.
At 50 hPa there is an ozone deficiency over the Eurasian continent.
At 50 hPa the distribution of ozone is similar with some contraction over the north Pacific and a clearer definition of the ozone deficient zone over the Eurasian continent.
The circulation of the air in the stratosphere is about an elongated core of high surface pressure located over the Eurasian continent stretching from Scotland to Mongolia. Within this cell very cold air that has little ozone but tracers of N2O descends from the mesosphere. N2O is primarily derived from soils due to organic decomposition. It is abundant in low latitudes where it scalps ozone to produce an elevated tropopause.