This essay addresses the question of whether tropical waters are likely to warm or cool in the last half of 2009. Necessarily it also addresses matters such as:
- The character of warming cycles in the tropics.
- The usefulness of the ENSO 3.4 Index as a proxy for tropical warming events.
- The driver of sea surface temperature change in the tropics.
- Change in the nature of this driver over time.
- The contribution of warming cycles in the tropics to global temperature change.
- The place of greenhouse theory in explaining global temperature change.
For a description of the data used for this analysis see Kalnay, E. and Coauthors, 1996: The NCEP/NCAR Reanalysis 40-year Project. Bull. Amer. Meteor. Soc., 77, 437-471. This data can be accessed at: http://www.cdc.noaa.gov/cgi-bin/data/timeseries/timeseries1.pl
Global temperature is strongly influenced by change in sea surface temperature in the global tropics. There is a lag of about six months from tropical to global peak. There is no argument as to the driver of global temperature on a year to year basis. Until recently many observers (including the UNIPCC) have maintained (without any justification whatsoever) that the ENSO oscillation is temperature neutral on decadal and longer time scales. That assertion is now widely questioned. We must ask how much, and whether all of the change in global temperature can be attributed to the cycles of warming and cooling in the tropics. The strong temperature gain between 1978 and 1998 has been attributed to man’s influence on the basis that “we know of no other reason for the change that has been observed.” That logic is now in question. Was something really obvious simply overlooked? There is still no evidence for the greenhouse induced ‘hot spots’ in the upper atmosphere. Is the UNIPCC assertion that the recent warming is due to the activities of man classic case of jumping to premature conclusions in the face of abundant evidence to the contrary.
Frequently the collapse of a solar cycle is associated with cooling in the tropics while the onset of a new cycle is associated with the initiation of a strong warming event. However, Cycle 24 is unusual. The sun is spotless even though 10.7cm radio flux has been increasing since late 1998. Just when is the big warming event to be expected and will it be as big as 1997-8?
Those who believe that anthropogenic greenhouse gases drive a relentless increase in atmospheric temperature eagerly await the next El Niño to re-establish their predicted warming trend.
In previous posts, and again here, I demonstrate a deterministic relationship between temperatures in the tropical STRATOSPHERE and sea surface temperature. Temperature in the tropical stratosphere varies with its ozone content. An increase in stratospheric ozone is associated with the slackening of the Antarctic vortex between July and January and the collapse of the Arctic vortex in March April, an event that varies in significance with the oscillating strength of the latter. Modulating the strength of the annual cycle there is an exaggerated biennial flux in temperature associated with a wind reversal in the equatorial stratosphere described as the Quasi Biennial Oscillation. On a much longer time scale, a strong increase in the temperature of the southern stratosphere occurred between 1948 and 1978 and a decline thereafter. The resulting climate shift of 1978 was manifestly responsible for the 20 year warming trend in sea surface temperature that ran through to 1998.
It is possible to demonstrate that the temperature of the tropical atmosphere between 200hpa and about 10hPa moves in a synchronous fashion. As it moves, the (very hard to measure) opacity of ice cloud above 200hPa must vary in such a way as to admit more or less sunlight. The fact that sea surface temperature is locked directly to the temperature of the atmosphere above 200hPa strongly suggests that the flux in ice cloud opacity is the factor involved in modulating albedo.
The tropics between 30°north and 30°south tends to be relatively free of low cloud. The map of the globe below shows amazingly low levels of outgoing long wave radiation from the cloudiest areas of the tropics where convection and resulting de-compressive cooling is the defining characteristic. Conversely, high levels of outgoing long wave radiation emanate from locations where descending, warming, relatively cloud free air lie over the vast expanses of the southern ocean and the subtropical North Atlantic. It is these cloud free areas that will expand and contract as the centres of tropical convection wax and wane in their activity.
Operationally, when the ozone content of the upper troposphere and stratosphere increases, the upper atmosphere warms, cirrus cloud evaporates allowing more sunlight to reach the ocean. As the ocean delivers more evaporation to the atmosphere the centers of ascent and descent see intensified activity. As the centers of descending air expand, so also is there an expansion of the cloud free area. The ocean warms. This warming and cooling activity, depending upon cloud cover, is modulated by a wholly autonomous process that changes the concentration of stratospheric ozone.
This post identifies the southern hemisphere locations that exhibit strong warming that initiates or contributes to generalized warming events.
Where is the warming activity concentrated?
Figure 2 compares global tropical sea surface temperature and sea surface temperature between 10° north and 10° south latitude. At issue is the question of what latitude sees the greatest warming. Is the warming confined to the Pacific and Indian Oceans? Is the warming confined to close equatorial latitudes? Is it due to a change in currents in the close equatorial zone? Is it due to the spreading of western Pacific Warm Pool waters over a greater surface area as the trade winds slacken? Is it due to reduced upwelling of cool waters along the western coasts of the great continents as the trade winds slacken? Is it due to warming of the ocean floor? In truth it is none of these as a moments examination of figure 2 will reveal.
Figure 2 shows that warming in the wider zone between 30°N and 30°S precedes that in the close equatorial zone. Accordingly, it must be change in the latitudes outside the close equatorial zone that accounts for the flux in temperature at the equator. All waters between 30°N and 30°S are driven equator-wards by the trade winds. The atmosphere can not warm the ocean except at the very surface but sunlight penetrates to 200-300 metres. Logic dictates that it is the flux in cloud cover outside the very cloudy Inter-tropical Convergence Zone that is responsible for warming cycles in tropical temperature.
Secondly, let’s note that tropical temperatures between 30°N and 30°S have been very close to the long term (January 1948- August 2009) average since 1999. The cooling event of 2008 plumbed a depth unreached in 2000 and the cooling event of 2009, brief as it was, all but matched it, if not in duration then certainly in terms of the temperature reached. Where is the warming?
Thirdly we note that peaks in temperature in the global tropics occur in the main at the end of southern summer (blue arrows). The sun is closest to the earth on December 21st. The southern ocean is more extensive and much cooler than the northern ocean at all latitudes. Furthermore, the Inter-tropical Convergence Zone is located north of the Equator for most of the year and the southern Trades and the configuration of the continents ensure that the northern hemisphere is the recipient of most of the benefit from the warming of the southern ocean. Figure 2 shows that the zone 0-10°north is slightly warmer than the zone 0-10°south most of the time, although manifestly not so in the strongest warming events like that of 1997-8. Given this dynamic, tropical waters must be expected to cool strongly during southern hemisphere winter in mid year.
However, it is apparent that the tropical ocean sometimes experiences anachronistic warming in mid and late year (blue circles and red arrows). How can this be? What causes it?
Warming late in the year
Figure 3 confirms the point that the early annual peak in tropical sea surface temperature (blue arrows) is always associated with strong warming of waters between 20° and 40° south latitude. It is therefore the warming of the southern waters that drives this annual peak. However it is also plain that the southern tropics do occasionally warm in mid and late year (see the green arrows). But, omplicating the picture is the presence of late year warmings (see red arrows) that are clearly not associated with generalized warming between 20° and 40° south.
Late year warming not associated with warming in subtropical waters in general
Figure 4 shows the relationship between global tropical sea surface temperature and sea surface temperatures in the ENSO 3.4 zone in the mid Pacific. The Niño-3.4 region is located at 5°N-5°S, 170°W-120W.
It is notable that when temperature in the ENSO 3.4 region is elevated we have late year heating events that are not associated with the warming of southern waters in winter. Notice that the early annual peak in global tropical temperatures frequently finds the ENSO 3.4 index at a minimum. Given the difference between the two data streams it is apparent that an index of ENSO 3.4 temperatures relates poorly to tropical and global temperature. ENSO 3.4 is a Pacific phenomenon that does not relate at all well to warming phenomena in the rest of the tropics or the globe as a whole. In terms of global temperature dynamics it’s a distraction and something of a red herring. The dynamics driving ENSO 3.4 temperature are not the same as those driving temperature in the global tropics.
This however, is not to say that what happens in the Pacific is irrelevant to the dynamics of tropical temperature change. The Pacific is an important theater, but not the only one.
Warming in the in-feed zone of the south east Pacific
Figure 5 compares anomalies in sea surface temperature in the global tropics with those in the in-feed zone in the south east Pacific. The in-feed zone is partitioned into two areas by latitude, separating 30-40°south from 20-30°south. Figure 5 also identifies late season warming events with red and green circles. A strong warming of the in-feed zone of the equatorial waters coincides with early annual warming events. But this in-feed warming also occurs and is responsible for late year warming on six of eight occasions.
Strong in-feed warming has been uniquely responsible for the spectacular increase in tropical sea surface temperature in both 2008 and 2009. The resulting increase in tropical temperatures will however be short lived because the south east Pacific is already cooling. On the other hand successive minima show an advancing trend from 2005 suggesting that, if this trend continues, strong warming of the in-feed and the equatorial zone zone may be possible next time round late in 2010.
Cause of warming in the in-feed zone
Figure 6 shows that in-feed warming extends over thirty degrees of longitude in northward trending waters at latitude 30-40° south. Figure 6 also identifies with red arrows warming associated with the periodic collapse of either the Arctic or Antarctic vortex customarily described either as a ‘sudden’ or a ‘final’ stratospheric warming. This phenomenon is described in the post: https://climatechange1.wordpress.com/2009/03/08/the-atmosphere-dancing-in-the-solar-wind-el-nino-shows-his-face/
The changing nature of the forces driving sea surface temperature in the south east Pacific in-feed zone is apparent in figure 7. After 1978 the range of latitudes responsive to change in stratospheric ozone increased to take in 30-40° south. The increase in the temperature of the upper troposphere and stratosphere prior to time was responsible (via change in ice cloud cover) for the increased extent, frequency and intensity of warming events that raised global temperatures between 1978 and 1998. However, 200hpaand 20hPa temperature in the global tropics and in the south east Pacific in particular has actually been in slow decline since 1983 and cloud cover in the upper troposphere must be expected to respond accordingly just so long as upper atmosphere moisture levels are adequate.
Figure 8 shows how sea surface temperature in the in-feed zone is locked to stratospheric temperature at 20hPa.
Change in the parameter driving cycles of sea surface warming and cooling
Figure 9 plots the moving 12 month average of 20hPa temperature at 10°north to 10°south and also the departure of each month’s mean from the period average for that month. This is a very important graph. It shows the dramatic change in the forces driving sea surface temperature over the period of record. And indeed, what changes there have been! Here is a list of the patterns that emerge.
- There are four, five or six warming cycles in stratospheric temperature per solar cycle. The nature of these warming cycles has changed over time.
- Cycle 18 produced relatively stable temperatures in the stratosphere.
- Strong peaks in stratospheric temperature occurred in 1963, 1971, 1983, 1992 and 2007.
- The strongest advances in stratospheric temperature occurred in the early stages of odd numbered cycles 19, 21 and 23.
- Much enhanced variability in temperature from month to month is seen to develop in solar cycles 22 and 23.
- Stratospheric temperatures are again on the increase in the last half of cycle 23.
- Cycle 20, when the globe cooled, was marked by declining temperatures in the stratosphere after solar maximum as was cycle 22.
It is abundantly evident that the basic parameter driving the warming of the tropical sea has changed dramatically over the period of record. Conventional climate science and the UNIPCC knows nothing of this.
It is apparent that cycles of warming in the tropics contributed strongly to the increase in global temperatures between 1978 and 1998. The forces that control the temperature of the stratosphere influence the flux in ice cloud cover in the subtropics and thereby the frequency and intensity of warming events in the tropics. The role of cirrus cloud in determining the flux of temperature at the surface is currently misunderstood. This misunderstanding is a product of reliance on greenhouse theory in complete defiance of the evidence that other factors overwhelm and negate the response to the increase in trace gas content. As the upper atmosphere warms in subtropical latitudes cirrus evaporates and the surface manifestly warms. It does not cool. The IPCC has it the other way round. It maintains that cirrus cloud traps heat and warms the surface. This theory is completely at odds with observation. It should be consigned to the scrapheap of intellectual thought along with Lysenkoism. It is Junk Science.
The behaviour of stratospheric temperature since 1948 is inconsistent with the notion of a closed system. Solar influences and in particular the condition of the polar vortexes is critical in determining the temperature of the stratosphere. Temperature change in the stratosphere propagates from high to low latitudes. The dynamic whereby water vapor is lifted into the stratosphere from a warm tropical ocean, influential because it dissolves ozone, is important in damping change in stratospheric temperature in equatorial latitudes. But, the temperature of the stratosphere at high latitudes is externally driven. Geomagnetic events and the intensity of solar irradiance are known to affect the concentration of erosive nitrogen oxides that enter the stratosphere via the polar vortexes and deplete stratospheric ozone.
Until the dynamics that control the ozone content of the upper atmosphere are fully elucidated the future of tropical and global sea surface temperature will remain unclear. Some atmospheric scientists assert that planetary waves generated by internal processes control the temperature of the tropical and polar stratosphere. The thread of that argument is fragile in the extreme.
In general, our understanding of the atmosphere is weak. Compartmentalizing of the atmosphere into discrete regions known as troposphere, stratosphere, mesosphere and thermosphere tends to inhibit focus on the all important interaction zones. This categorization is no more valid or useful than the notion that there are discrete zones characterized by quite different and stable climates on the surface of the Earth.
The influence of solar activity is plainly important in driving air temperature above the 200hPa level (about two thirds of the way into the troposphere). Ice cloud is also found in the stratosphere..
The upper atmosphere has an electrodynamic dimension (related to the increasing presence of plasma with elevation) that renders it susceptible to the influence of the flow of charged particles from the sun. This may be responsible for the change in surface pressure at the poles in relation to that at the equator and the phenomena whereby the upper tropical stratosphere suddenly cools as the polar stratosphere warms.
The atmosphere is asymmetric between north and south in part due to the presence of the Antarctic ice mound and the relative abundance of land at high latitudes in the northern hemisphere. The distribution of land and sea is a strong contributor to atmospheric dynamics. So, the hemispheres are essentially very different, a strong factor influencing atmospheric dynamics.
The atmosphere is not amenable to modeling that treats the globe as a closed system. Our understanding of atmospheric processes is elementary. Mathematicians who do not appreciate that the basic parameters driving climate are externally imposed and forever changing, are a hindrance to progress and best employed elsewhere.
It is unnecessary to invoke the increase in the concentration of trace gas concentration in the atmosphere as a cause of surface temperature change. This pattern of thought is nonsense. Natural processes are at work and these owe nothing to the activities of man. It is the height of folly to drive up the price of fossil fuels in pursuit of a furphy.
Footnote: A furphy, also commonly spelled furfie, is Australian slang for a rumour, or an erroneous or improbable story.
SEPP Editorial #26-2009 (8/22/09)
The Big Global Warming Debate
By S. Fred Singer, President, SEPP
Solar power is good for hot water systems, remote properties, navigation beacons, recharging portable batteries, growing grass and drying the washing. Wind power is good for pumping water, flying kites and racing yachts. Neither can be relied on to run the trains, the factories, the smelters or the hospitals. Any society foolish enough to rely on these medieval energy sources deserves to freeze in the dark.
Naturally, if enough money is extracted from consumers or taxpayers, we could build enough storage capacity or backup generating capacity to provide continuous power from these intermittent power sources. But the cost is prohibitive because the backup facility needs to cope with 100% of the Green Power capacity. This duplication doubles the capital cost of Green Power, but neither the Green Plant nor the backup plant is used efficiently: one or the other is always idle.
If Australia is stupid enough to mandate 20% of the electricity market for Green Power, electricity costs will escalate, backup gas prices will soar, industry will emigrate and jobs will disappear. If the market is unwilling to build Green Power facilities without mandates or subsidies, there is a good reason for it.