Saturday, January 22, 2022


 An Alternative Climate Change Theory

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all earlier videos  at

The transcript for this video is below

Welcome back everyone.

Surprising to many, climate change over the past 10 thousand years has acted completely opposite of what the CO2 hypotheses predicted.

So here in part 4 of my educational video series, I present a much-needed alternative hypothesis that is 100% supported by evidence over the past 10,000 years. I call it the dynamic warm pool, La Niña, Intertropical Convergence Zone hypothesis, or just the Warm Pool Theory for short.

As Rosenthal 2016 has argued, it only requires very small changes in solar heating.

The earth's average temperature is a balance between heating from absorbed solar energy and the rate of cooling as energy is radiated back to space.

The warm pool theory argues ocean dynamics determine the earth's heat storage and heat ventilation and that controls the earth’s rate of cooling.

The function of the warm pool is analogous to a home’s hot water heater and determines how much heat reaches the rest of the world. When a home's hot water heater is fully charged, then there's adequate hot water for every sink, dishwasher, and shower. But drain that hot water heater and you suffer a cold shower. Warmer water gradually returns as the hot water heater recharges.

Likewise, the Little Ice Age drained the warm pool. Now our current warming trend is simply the net effect of a recharging warm pool.

Because oceans can store huge amounts of heat, but the atmosphere cannot, and because the upper 10 feet of the world's oceans contain more heat than the entire atmosphere, solar driven ocean dynamics are truly the climate control knob. The warm pool theory explains the past 10,000 years of climate change, an explanation that CO2 driven climate models have repeatedly failed to account for.

The Indo-Pacific warm pool is often called the heat engine of the world. It is defined by waters that are 28ºC or 82ºF or warmer, and is primarily located in the western Pacific as well as the eastern Indian Ocean

The intense convection over the warm pool drives the region's Hadley circulation and transports heat via the atmosphere from the tropics towards the poles.

Convection requires a minimum ocean surface temperature of 26ºC, and widespread deep convection requires 28ºc or more. Smaller warm pools will generate less convection and thus less global. Warming.

In addition, the strength of the warm pool also determines how much warm water is transported from the tropics to the arctic via several dynamics that integrate into the global conveyor belt.

(One point I didn't emphasize enough in this video but am adding here, is as the re-charging of the warm pool increases heat in the Great Ocean Conveyor Belt, and that heat gets transported into the Arctic, it creates a positive temperature feedback that melts more Arctic sea ice which allows the great quantities of heat stored in the Arctic Ocean to more readily ventilate. It is that short term ventilation of heat that has biased the global average temperature. Like an El Nino event, that heat ventilation paradoxically cools the ocean while warming the air yet this "dynamical warming" is falsely attributed to radiative heating from rising CO2.

There are 4 previous videos that discuss heat transport into the Arctic, the first video is at

And all 4 can be found at

It is well established that on average the tropics receive far more solar energy (represented by the blue curve) than the tropics radiate back to space (represented by the red curve).

That's because significant tropical heat is transported to the poles where it is radiated back to space. That transported heat also warms the poles, which become much warmer than by solar radiation alone. Thus, a stronger warm pool generates a higher global average temperature by transporting heat across the globe via convection and the ocean conveyor belt.

Several peer-reviewed papers have examined how the warm pool has changed since the last glacial maximum. The illustration here is from dang 2020.

Despite low CO2 concentrations, temperatures of the warm pool began heating up 25,000 years ago and peaked about 10,000 years ago in a period known as the early Holocene.

Then for the past 10,000 years the oceans cooled until a slight warming trend began over the recent 300 years

In contrast, sea surface temperatures and the global average temperature lagged the warm pool warming,

Suggesting it is deep ocean warming that drive atmospheric warming.

The sun's Milankovitch orbital cycles of obliquity and precession seem to correlate well with the warm pool's long term temperature trends but can’t explain the last few hundred years. Those orbital cycles do not add to the earth's annual insolation. The peak of those cycles in the early Holocene did cause warmer northern hemisphere summers but were balanced by colder winters. In addition, if precession drives global temperatures, our current temperatures should be as cold as they were 22,000 years ago. I introduced the mechanics of these cycles, in part 3 "how the sun and the ITCZ controlled climate and civilization collapses"

Cooling of the Holocene warm pool can be explained by the ITCZ's southward migration that increases El Niño events which ventilate and drain warm pool heat.

The ITCZ integrates global energy inputs and outputs,and accordingly shifts its average location towards the warmest hemisphere. Thus, small changes in solar energy can drive the migration of the ITCZ.

As the ITCZ migrated southward, it increased the frequency of El Niño events that cool the warm pool and contributed to the Holocene cooling trend.

Conversely, it can be inferred that any northward ITCZ shift would result in fewer El Niños and more La Niña-like conditions that heat and enlarge the warm pool.

Although the exact reconstruction of global temperatures varies depending on the models and data that a researcher employs, all agree there has been an 8000-year cooling trend and that is the exact opposite of what CO2 driven climate models simulate.

The erroneous climate models are driven by an 8000-year trend of increasing CO2, which puts those models at odds with evidence-based climate change

In contrast to the Holocene cooling trend, all relevant researchers have found the warm pool has been expanding since 1900.

And this expansion coincides with a more La Niña-like Pacific Ocean with fewer El Niño events than during the Little Ice Age.


Here is a closer look at the dynamics that control the warm pool and the effects of the ITCZ and El Niños. Trade wind-driven equatorial currents bring heated water to the warm pool.

These currents are the north equatorial current, designated here as NEC, and 2 branches of the south equatorial current designated SEC.

The equatorial currents generate higher sea levels in the Pacific which pushes warm water through the maze of channels around the islands of the maritime continent, comprising a westward current known as the Indonesian throughflow. Much of that through flow joins the Indian ocean's south equatorial current that is part of the ocean conveyor belt. Some throughflow water circulates through the northern Indian ocean, enhancing an Indian ocean warm pool,

While some flows join the Leeuwin current that flows southward along the west coast of Australia. During a strong La Niña this current is amplified producing what Australians call a Ningaloo Niño.

While the warm pool's overflow through the Indonesian through flow modulates its size, it is the eastward north equatorial counter current that truly controls the warm pool's size which then modulates the throughflow and warming of the ocean conveyor belt, The stronger the north equatorial counter current the more rapidly the warm pool is drained.

The strength of the north Pacific gyre controls the draining of the warm pool.

The gyre is driven by the north trade winds that drive the north equatorial current on the gyre's southern border, while the westerly winds drive the gyre eastward on the gyre's northern border. The north equatorial current contributes a limited amount of water to the warm pool because much of the current veers northward into Kuroshio current bringing added warmth to Alaska.

Since the 1980s, many researchers have reported that a strong gyre drains the warm pool by enhancing the counter current.

Most recently researchers confirmed the connection between the gyre strength, the southward ITCZ migration during the Little Ice Age and an enhanced counter current that drained the Little Ice Age warm pool.

So, what's the role of thee ITCZ? In the age of satellites, the ITCZ is defined by a band of heavy clouds encircling the earth. But centuries ago, sailors identified the ITCZ by the doldrums which stranded many a ship for days and weeks. The ITCZ's vertically rising air creates relatively motionless surface air with no movement to the east, west, north, or south. Thus, the doldrums allow a counter current to flow eastward without being opposed by the westward trade winds 

As a result, a shifting ITCZ can determine the strength of the counter current and size of the warm pool on all time scales from seasons to ice ages. 

The two branches of the south equatorial current provide about 66% of the warm water to the warm pool. Because the ITCZ's average position over the Pacific remains to the north, there is only a very weak south equatorial current, here designated SECC, that sometimes disappears completely. So equatorial counter current has a minimal impact on the warm pool. 

Not only does the ITCZ drive the strong north equatorial counter current but also a deeper eastward undercurrent that drains deeper waters of the warm pool. 

How does the sun and greenhouse warming affect the warmth of the equatorial currents? The warm pool waters originate from the high-pressure regions created by the Hadley circulation. The descending air in those high pressure-systems are dry, and thus few clouds are formed and amplifies solar heating. The lower amounts of water vapor, the major greenhouse gas, also allows more heat waves to escape back to space, reducing any greenhouse warming. So, it is accurate to claim increasing warm pool heat is driven by solar heating. 

All the dynamics in a La Niña-like ocean are illustrated here.    An official La Niña happens when temperatures in the Niño 3.4 regions are at least a half degree Celsius cooler than average for 3 months. Whether during a neutral El Niño Oscillation year or an official La Niña year, the same dynamics increase the warm pool. 

Accordingly, the western Pacific experiences higher sea levels that feed the Indonesian throughflow and ocean conveyor belt. More warm water gets stored deeper in the west Pacific warm pool deepening the thermocline. Strong trade winds cause upwelling of cooler deep waters in the eastern Pacific, causing a large east west temperature gradient of about 6-7 degrees Celsius between the warmer western warm pool and the cooler upwelled waters of the eastern Pacific. That large temperature gradient defines a La Niña-like ocean. This temperature gradient amplifies the trade winds which further reinforces La Niña conditions.

All climate models based on the physics of CO2 warming have predicted that rising CO2 would have little effect on warm pool surface temperatures, arguing CO2 would preferentially warm the eastern Pacific where dryness had reduced greenhouse warming, and thus reduce the temperature gradient But this has not happened, as the large temperature gradient has on average remained or increased in accord with a currently growing warm pool. 

In 2019, Seager published a paper showing that by using different physics, the lack of eastern Pacific warming was consistent with CO2 theory. Apparently, the choice of which science to follow is quite arbitrary So, with amplified trade winds maintaining strong La Niña-like conditions, what triggers the switch to an El Niño every 3 to 7 years. The short answer is the ITCZ 

The ITCZ doldrums enable an amplified eastward equatorial countercurrent that results in El Niños As the ITCZ moves southward the rising air within the ITCZ also triggers the intense convection in the Indian ocean of the 60 to 90-day Madden Julian Oscillation that produces westerly wind bursts Those westerly wind bursts can initiate a kelvin wave of eastward flowing warm pool water. 

The resulting El Niño events then drain the warm pool and cool the ocean's sub-surface waters.    Enough 26+ degree warm pool water moves eastward to also shift the location of intense convection affecting global weather. The warm pool's stored sub-surface heat is brought to the surface in the central and eastern Pacific where it ventilates causing a temporary spike in the global average air temperatures. That reduces the east west temperature gradient, which defines an El Niño-like ocean. A smaller temperature gradient weakens the trade winds reducing the volume of warm water pumped into the warm pool.    Upwelling is reduced, maintaining a warmer eastern Pacific, 

Looking at just the past 2000 years, Oppo's 2009 temperature reconstruction shows the recent warm pool temperatures (shown here in black), began increasing in the 1700s before the rise of industrial CO2. Oppo also compared warm pool trends to Michael Mann’s 2008 global temperature reconstruction, shown in red. Both reconstructions show similar long-term variations except Mann’s last 100 years that he attributes to rising CO2.  However, the warm pool was as warm 1000 years ago during the Medieval Warm Period, as it is today, despite lower CO2 concentrations. 

However, the warmer Medieval warm pool does correlate with a La Niña-like ocean and an ITCZ that was located further north.  

During the Little Ice Age, the warm pool cooled associated with sunspot minimums and the southward migration of the ITCZ. The ocean entered an El-Niño like state, (as indicated by coral proxies from Cobb 2003 and other researchers), indicating ocean dynamics were draining the warm pool. 

 Since the 1700s, as the ITCZ moved back northwards, the ocean experienced fewer ventilating El Niños, and the warm pool began warming and expanding 

So, here's how to interpret a graph of the past 50 years of global average temperatures.  Putting aside changes in land surfaces that also increase temperatures via dynamics such as urban heat islands, the most parsimonious explanation for the observed warming trend is there are currently fewer El Niños than during Little Ice Age, and more La Niña-like years that has increased the heating dynamics to support a growing warm pool. The warming trend simply reflects the recharging of the earth's hot water heater that was drained during the Little Ice Age. 

The transitory air temperature spikes are caused by El Niños discharging stored heat, which temporarily cool the ocean. 

So, what does the future hold? It’s hard to know. The scientific community is divided on predictions regarding more or fewer future El Niños 

But the next few decades should provide some evidence that could refute or support the warm pool hypothesis. So, teach your children to be on the alert and think critically. 

If low solar output continues with low sunspots as some predict, then, if the ITCZ is truly sensitive to such small radiative changes, the ITCZ should move further southward, and temperatures will approach Little Ice Age conditions. 

However, if solar output increases as others predict, the ITCZ should edge northwards, and the warm pool will continue to expand, and temperatures will approach those of the medieval warm period. The good news is since there was no climate crisis one thousand years ago, there won’t be one that happens in the near future, and the effects of CO2 will continue to be insignificant. 

So up next: will be part 5 of how pressure systems control the climate: the cause heatwaves

Sunday, January 9, 2022


       How Pressure Systems Control Climate Part 3: 

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To find all my videos and the earlier parts of this series,  go to youtube channel

the transcript is below

Welcome back and best wishes for the new year

Today in part 3 of how pressure systems control the climate, I look at how the sun controls the location of the intertropical convergence zone or ITCZ and how a shifting ITCZ and its linked high-pressure systems have led to the rise and fall of many civilizations.

To ensure we properly adapt to future devastating weather events, we must correctly understand natural climate change. Natural weather disasters, much worse than those in recent times, have happened throughout history and will continue to happen regardless of any changes in human CO2 emissions.

Warming from the sun, affects climate very differently than warming from a CO2 greenhouse effect.

Solar radiation can penetrate the ocean as deeply as 200 meters compared to CO2's infrared radiation that barely penetrates a micron of the ocean surface.

Due to changes in the earth's orbit, the direct rays of the sun which can heat the earth's surface up to 1000 w/m2 at noon on a cloudless day. The sun's orbit shifts the location of that warming by 5000 kilometers in a year. By shifting the ITCZ, atmospheric and ocean circulations are also altered.

In contrast well-mixed CO2 warms the earth's surfaces equally.

So, let’s examine the sun's relationship to climate

The Hadley circulation discussed in part 2, links the rainy ITCZ and dry high-pressure systems, and provides the general framework and background for all the more transitory weather events.

The sun's orbital cycles (the Milankovitch cycles) shift the ITCZ and Hadley circulation. Here I focus on the ITCZ shifts since the end of the ice age's last glacial maximum, a time when the ITCZ had been shifted further southward than it is today.

As the ITCZ moved northward, driven by changes in solar heating, the glaciers began melting and the northern hemisphere experienced what scientists call the Holocene Thermal Maximum, roughly lasting between 6 and 10 thousand years ago. Temperatures rose about 3 degrees Celsius warmer than today. Subsequently, the ITCZ and its tropical rainfall shifted much further north than today

Driven by the sun's Milankovitch cycles, a steady 6000-year migration of the ITCZ towards it last glacial maximum southern extent then ensued, coinciding with a cooling trend known as the neo-glaciation. That ITCZ migration and its linked high-pressure systems also changed the locations of the earth's deserts and droughts and civilization collapses.

As the ITCZ migrated southward it also caused greater climate variability.

The ITCZ’s southward migration increased the number of El Nino events, and those events altered the earth's temperature balance, which in turn created feedbacks that further altered the ITCZ 's location.

How evolving El Ninos and other ocean oscillations altered pressure systems and generated the greater weather variability seen today will be discussed in part 4.

Milankovitch's obliquity cycle refers to the changes in the tilt of the earth's axis. If the axis was perpendicular to the sun's rays, there would be no seasons and the arctic would be in a perpetual twilight.

However, currently the earth's axis is tilted 23.5 degrees which causes more sunlight and warmer temperatures to move northward, producing summer conditions when the northern axis is pointed towards the sun. Over the course of about 41,000 years the earth's axis oscillates between 24.5 degrees, which will cause the warmest artic summers, then shifts to 22 degrees causing the coolest arctic summers

While keeping the same tilt, the axis also wobbles. This wobble is Milankovitch's precession cycle causing the axis to go from pointing at the north star, Polaris, as it does today, then circling to point at other stars over a period of about 26,000 years

In June the earth's axis points towards the sun causing our northern hemisphere's summer. As the earth revolves around the sun the northern axis continues to point towards the north star but by December it points away from the sun causing the northern hemisphere's winter while summer conditions shift to the southern hemisphere.

Surprisingly, the northern hemisphere experiences winter even though the earth's orbit is closer to the sun than at any other time.

Due to precession, 13,000 years into the future, as well as 13,000 years ago, the north axis was pointed towards the sun at the same time it was closest to the sun. It is believed that such an alignment of obliquity and precession maximized the Arctic's solar heating and triggered the melting of the ice age glaciers.

But as the orbital factors transitioned to their cooler phases, arctic sea ice and glaciers began to return and the earth entered its recent 6,000-year cooling trend, the neoglaciation, and the ITCZ migrated southwards

The extent of the location of the sun's hottest direct rays defines the tropics and the tilt of the earth's axis determines how far poleward that maximum solar radiation, as well as the ITCZ, can migrate.

The current 23.5-degree tilt of the axis causes the sun to be directly over the Tropic of Cancer, 23.5 degrees north of the equator, during the northern hemisphere's summer.

Due to ocean circulation effects, the ITCZ does not reach the Tropic of Cancer over the ocean as it does over land. During the southern hemisphere's summer, the direct rays reach the tropic of Capricorn 23.5 degrees south of the equator

Due to high obliquity, 7000 years ago the ITCZ and the north Atlantic subtropical high-pressure system referred to here as the NASH, was located much further north than today. The clockwise circulation of the NASH forces the westerly winds northward, shown here as the dashed line. Without rains from the ITCZ or westerlies, the Iberian Peninsula was extremely arid. Elsewhere, the northerly migration of the summer ITCZ and strengthened NASH also moved the rainy westerlies away from Scandinavia and towards Iceland

By 5000 years ago, Iberia's Mediterranean climate began to evolve as the ITCZ, and NASH migrated further southward. When ITCZ and NASH moved further south over Africa in the winter, the westerly winds could bring rains to Iberia

However, when the ITCZ and NASH moved northward in summer, the westerly winds were pushed northward causing Iberia to experience dry summers So, like California, as discussed in part 2, Iberia similarly evolved into a Mediterranean climate with hot dry summers and cool wet winters.

But the ITCZ 's southward migration now devastated northern Africa

When the ITCZ was centered closer to northern Africa the Sahara Desert was a lush grassland with large lakes. Cave drawings from southern Algiers depict abundant grazing antelope and cattle and giraffes. But driven by decreasing obliquity and precession, the steady southward shift of the ITCZ and NASH, initiated the earth's greatest drought known to humans, converting a humid African savannah

Into the greatest desert on earth --the Sahara Desert

It should be noted, because the ITCZ today is not as far south as it was during the ice age's glacial maximum, today's Sahara is not quite as extensive as it was during the ice age. If obliquity is indeed the primary controller of the ITCZ, expanding desertification can be expected over the next 10,000 years

As the rich grasslands of northern Africa converted to desert, the large human populations it supported were forced to migrate. The genetics of Mediterranean people suggest many Africans moved into southern Europe.

The increasing dryness forced other people to settle in the major river valleys where reliable water could be obtained such as the Nile Valley.

This great drying happened at similar latitudes, and other great river civilizations developed, in Mesopotamia, the Indus River valley, and yellow river valley.

The once lush region just south of the Sahara, known as the Sahel, seen here in light orange, did not turn to desert, but became increasingly vulnerable to small migrations of the ITCZ and the increasing climate variability.

That forced the Bantu speaking people of northwest Africa to migrate southward Either conquering or integrating with existing tribes throughout southern Africa

The summer warmth currently moves the ITCZ far enough to the north, that rains from the summer monsoons can reach the Sahel. But in the winter the ITCZ moves south again. While gifting southern Africa with rain, the Sahel experiences a cool season drought. And whenever the ITCZ remains too far south, either driven by ocean oscillations or changes in sunspots, it has brought major devastating droughts to the Sahel every century since the 1600s.

The tragic Sahel droughts of the 1960s to 1980s required massive world-wide relief funds to minimize the starvation experienced by people of the Sahel who depended on rainfall for farming and grazing.

Why did the ITCZ move further south?

One explanation is the ITCZ always migrates away from cooler regions and towards warmer regions. The most relevant studies pointed to the Atlantic multidecadal oscillation that caused cooling waters in the north Atlantic (as illustrated here in blue) and warming waters in the south Atlantic.

Climate scientists from NOAA also tested for effects from greenhouse gases but reported that the IPCC’s climate models failed to simulate those contrasting ocean temperatures or the ITCZ 's southern shift suggesting the droughts were "likely of natural origin"

The major drought events also coincided with small reductions of solar radiation associated with sunspot minimums

The Sahel's major Little Ice Age droughts of the 1600s and 1700s coincided with the Maunder sunspot minimum

The 1830s drought with the Dalton Minimum.

The 1910s drought again with low sunspots. Then as sunspots increased the Sahel received more rain culminating with a decade of steady rains in the 1950s.

But sunspots declined again resulting in the droughts of the 60s and 70s Then wetter weather returned in the 90s as sunspots increased

But as 21st century sunspots have approached the same low numbers as the 1910s, the Sahel has recently experienced 3 droughts between 2002 and 2012

The ITCZ and solar cycles are global phenomena, so as expected, the ITCZ shifts also affected people of the Americas. The Mayan population centers occupied Mexico’s Yucatan peninsula. There, situated at the northern limits of the ITCZ, summers brought abundant rains.

But during winter the ITCZ moved far to the south bringing winter drought. So, the Mayans adapted to winter dryness and increasing ITCZ variability by building extensive reservoirs and irrigations canals

But as the ITCZ continued to move southward, the Mayans began abandoning their cities around 200AD. And Mayan society finally collapsed by 800AD

As the southward migrating ITCZ approached the Little Ice Age between 1500 and 1800 AD, the Yucatan experienced increasing dryness and weather variability.

Droughts that devastated the people of the Sahel during the little ice age also happened all around the sub-tropical latitudes. In the 1400s the Mayan culture, and Aztecs of central Mexico suffered massive drought-induced famines . The Little Ice Age reduced the North American monsoons, and droughts devastated New Mexico's Pueblo culture. The drought of 1638 prompted a revolt by Pueblo people against the Spanish. . Little Ice Age droughts brought by the contraction of the Asian monsoons caused Cambodia's Khmer empire to abandon its capital of Angkor in 1431

And as the Little Ice Age droughts dislocated more and more societies, china's Ming dynasty expanded and fortified the great wall to prevent a growing number of invaders. But the droughts finally triggered the downfall of the Ming dynasty in 166 The changes in the ITCZ have increased the El Nino cycles which also alter the locations of dry and wet pressure systems which exacerbates droughts and floods around the world So up next: part 4 of how pressure systems control the climate: how El Nino and ocean oscillations influence droughts and floods

Until then embrace renowned scientist Thomas Huxley’s advice: 

 “Skepticism is the highest of duties; blind faith the one unpardonable sin"

Monday, January 3, 2022


Please watch the video:

The transcript is below.

See part 1 


Welcome back & Happy New Year 

Today I'm presenting part 2: how pressure systems control climate, focusing on the shifts in the intertropical convergence zone, or ITCZ, and why warmer temperatures attract more rain and thus why the ITCZ determines the location of both rainforests and deserts

Mainstream media's narrative suggests that global warming increases evaporation and thus makes worse droughts

But science flips that warming narrative on its head. As you will see conclusively, it is drought that causes higher temperatures.

And it is the reduced transport of moisture from the oceans to the land that causes drought.

You will see that during the coldest periods of the last 10,000 years, societies experienced the worst droughts, and contrary to media narratives, the science shows warmer temperatures will bring more rain

The ITCZ is easily recognized from satellite imagery showing a belt of clouds encircling the earth. It moves northward and southward with the seasonal position of the sun and determines what tropical regions experience a wet season or a dry season

In the northern hemisphere as summertime warmth moves north, the ITCZ, seen in red, brings the rainy season to the northern tropics, while south of the equator, cooler temperatures experience seasonal drought

In the southern hemisphere's summer, the ITCZ then moves southward, as seen in orange, while regions north of the equator experience seasonal drought On average the ITCZ migrates between 9 degrees north and 2 degrees north over the pacific and Atlantic oceans, but it migrates further north and south over Asia and Africa because land masses heat up faster than the ocean

Thus, over the lands bordering the Indian ocean, the ITCZ brings rainfall further poleward, on average migrating between 20 degrees north and 8 degrees south,

Published science shows that during cooler periods, such as the little ice age, that great width of the tropical rain bands contract, reducing the extent of monsoon rains

The little ice age was the earth's coldest period in over 10,000 years, yet despite global warming theory, it created some of the worst droughts, droughts that caused the collapse of many societies such as the Ming dynasty in china and the Khmer empire in Cambodia

The ITCZ represents the dynamical region that drives energy and momentum from the equator towards the poles and drives the Hadley atmospheric circulation

The ITCZ is the region of intense convection where moist air rises, then cools & precipitates heavy rainfall to regions below, enabling the world's tropical rainforests

The remaining dry air then diverges towards the poles where it sinks between 20 & 40 degrees poleward of the equator, generating regions of dry high-pressure that marks the edge of the Hadley circulation

This global map of precipitation illustrates the location of heavy rainfall from convergence zones (seen in reds and dark blue) around the equator And the regions of dry high-pressure systems symmetrically located north and south of the equator shown in yellow

A map of the earth’s great desert regions shows the correlation between deserts and the Hadley high pressure systems

I've overlayed the pressure systems to see this more clearly The high-pressure systems border the western edge of the USA’s western deserts and South America's Atacama They border west of the Sahara in northern Africa and the Kalahari in southern Africa And border the west of Australia's deserts

High pressure systems create warmer temperatures in several ways. The dry descending air in a high-pressure system produces clear skies

Without clouds or mist to block out sunlight, surfaces are heated more strongly by solar radiation

Water vapor is a greenhouse gas. So, without clouds and reduced water vapor more infrared heat escapes directly to space so clear skies also reduce the greenhouse effect. Nonetheless increased solar heating has a greater warming impact and offsets any decreased greenhouse effects

Even if there was no increase in solar or greenhouse radiation an increase in dryness amplifies temperatures

Known as specific heat, scientists determined that different substances require different amounts of energy to increase that substance's temperature To raise one kilogram of water by one degree Celsius requires 4200 joules. Joules is just a measure of energy.

To raise one kilogram of sand one degree requires much less energy, just 830 joules. Thus, by removing a kilogram of water from the land's surface the energy that would have raised water by one degree, will instead, raise the sand by 5 degrees.

In addition, over 2 million joules of energy are required to evaporate a kilogram of water without raising the temperature. These dynamics are just one reason why average temperatures can be unreliable science. An average temperature does not reflect changes in radiation from added carbon dioxide, unless all temperature effects induced by dryness are first accounted for. And that is not being done.

High pressure systems further generate regions of dryness by blocking the westerly flow of moist winds from the ocean to the land

High pressure systems cause the winds in the northern hemisphere to circulate in a clockwise manner, thus deflecting moist winds from the west northwards. For example, the pacific high-pressure system strengthens each summer because descending winds more readily descend over a cooler ocean relative to the warmer land.

By deflecting moisture northwards, the strengthened summer high causes California to be dry from June thru October, while simultaneously bringing summer rains to drench the coasts from Oregon to Alaska

Because this dryness amplifies temperatures, Death Valley in southeastern California still holds the record for hottest observed air temperature, reaching 134 degrees Fahrenheit on July 10th, 1913, long before any significant rise in CO2

The world's Mediterranean climates (shown here in red) are symmetrically located around the equator centered between 30 & 40 degrees north and south of the equator.

All Mediterranean climates are characterized by hot dry summers and cool wet winters. The opposite of tropical seasons As the ITCZ moves northward each summer, so do the high-pressure systems of the Hadley circulation cooler ocean surfaces relative to warmer land intensifies the highs which block the flow of moisture from the ocean to the land This is why the naturally dry summers in California and Greece and all Mediterranean climates are highly susceptible to wildfire As the ITCZ moves southward during the winter, so do the high-pressure systems, and as the highs weaken it allows ocean moisture to bring winter rains to the land

What might seem peculiar is that Mediterranean climates are restricted to relatively narrow bands along the coast

The reason Mediterranean climates don’t expand further inland is because the warmer land temperatures of summer create a low-pressure system that draws in the monsoonal rains from elsewhere

The North American monsoons draw moisture from the Gulf of California and Gulf of Mexico As seen by the weather data from Albuquerque, New Mexico, the greatest precipitation is brought inland during the hottest months of July thru September. 

Like the ITCZ transport of rains, summer monsoons illustrate how higher temperatures bring more moisture, not drought.

So up next: Part 3 How the Sun Controls the ITCZ 

Until then embrace renowned scientist Thomas Huxley’s advice:

“Skepticism is the highest of duties; blind faith the one unpardonable sin"