Guest Post from Jim Steele
From What’s Natural? Column
published in Pacifica Tribune June 26, 2019
I was recently asked if the record June 2019 heat in the San Francisco Bay Area validated CO2 driven climate models. Surprisingly climate scientists have now demonstrated the heat wave was largely due to an intrusion of record cold air into the Pacific Northwest. How?
Basically, the winds’ direction controls the San Francisco Bay Area’s weather. In summer, California’s inland regions heat faster than the ocean, so the winds blow inland from the cooler ocean. Those onshore winds bring cooling fog, our natural air conditioner. Later, as the sun retreats southward in the fall, the land cools faster than the ocean. Seasonal winds then reverse and blow from the cooling land out to sea. Those winds keep the fog offshore. Without fog, San Franciscans finally enjoy pleasantly warm days in September and October. In northern California those strong offshore winds are called the Diablo winds. Although Diablo winds bring welcome warmth, those winds also increase wildfire danger.
Typically, inland California heats up in June drawing in the fog. But that temporarily changed when a surge of record cold air briefly entered Washington state and then moved down into northeastern California and Nevada. Dr. Cliff Mass, a climate scientist at the University of Washington, studies the Diablo winds. On his popular weather blog, he discussed how that intruding cold air created an unseasonal burst of Diablo winds that then kept the fog offshore. Without cooling fog, solar heating increased temperatures dramatically. According to Accuweather, San Francisco’s maximum temperature on Friday June 7th was 67 °F, skyrocketed to a record 97 °F by Monday and then fell to 61 °F three days later as onshore winds returned.
Such rapid temperature change is never caused by a slowly changing greenhouse effect. Nevertheless, the media asks if rising CO2 concentrations could have contributed to the higher temperatures or made the heatwave more likely?
Although definitions vary, the World Meteorological Organization defines a heat wave as 5 or more consecutive days of prolonged heat in which daily maximum temperatures are 9+ °F higher than average. Assuming the rise in CO2 concentration increased all temperatures relative to the 20th century average, it is believed maximum temperatures are more likely to exceed that 9 °F threshold. But heatwaves are not caused by increasing greenhouse gases.
The science is solid that greenhouse gases can intercept escaping heat and re-direct a portion of that heat back to earth. That downward directed heat reduces how quickly the earth cools, and thus the earth warms. However, heat waves typically occur when greenhouse gas concentrations are greatly reduced. Eighty percent or more of our greenhouse effect is caused not by CO2, but by water vapor. Satellite data shows the dry conditions that accompany a heat wave actually reduce the greenhouse effect because drier air allows more infrared heat to escape back to space. However, like less fog, less water vapor and less clouds allow more solar heating. So despite the increase in escaping heat, increased solar heating dominates the weather and temperatures rise.
The important contribution of dryness to heat waves helps explain why the USA experienced its worst heat waves during the 1930s Dust Bowl years (see EPA Heatwave Index above). Furthermore, the EPA’s heat wave index appears totally independent of rising CO2 concentrations. Dryness also helps to explain why the hottest air temperature ever recorded anywhere in the world happened over a century ago in Death Valley on July 10, 1913; a time of much lower CO2 concentrations.
To summarize, an intrusion of record cold air into the Pacific Northwest generated unseasonal Diablo winds in northern California. Those offshore winds prevented the fog from reaching and cooling the land. In addition, because the Diablo winds are abnormally dry, solar heating of the land increased. Those combined effects caused temperatures to temporarily jump by 30 °F.
Lastly, not only can Diablo winds cause heatwaves, Diablo winds will fan small fires into huge devastating infernos such as the one that destroyed Paradise, California. Fortunately, there were few wildfire ignitions during this heat wave. To be safe, Pacific Gas and Electric had shut off electricity to areas predicted to have high wind speeds. So Dr. Mass mused, that because colder temperatures generate the destructive Diablo winds, climate warming may have some benefits.
Jim Steele is retired director of the Sierra Nevada Field Campus, SFSU
and authored Landscapes and Cycles: An Environmentalist’s Journey to Climate Skepticism
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CBC Journalist Nicole Mortillaro continues to mislead her readership through selective parsing of scientific literature and obfuscation of the heat wave synoptic meteorology in order to promote the climate change agenda.
https://www.cbc.ca/news/technology/european-heat-wave-1.5190952
Just like any meteorological event, including floods or heatwaves, a 100 y flood means that every single year, this type of flood has a 1% chance to occur. It can therefore re-occur a few years in a row. Abusing the selective Meteo France diagram conveniently starting from 1947 and thus omitting some of the highest heatwaves of the 20th century (the great 1911 heatwave and in the 1930s on June 23, 1935 it was 52 C in Zaragoza Spain), is trying stretching attribution. Other scientists interviewed are more prudent and serve the usual disclaimer “the event may not be caused by but is consistent with climate change” line, a profoundly inane statement since any situation is always, by nature, consistent with an ever changing climate, one way or another. Mortillaro takes that directly to the bank.
Curiously Google algorithms do not seem to offer readily any information older than 1947…
None of these facts inform Mortillaro’s writing. Instead, she selects tweets by Stefan Rhamstorf, a scientists from PIK, one institute that has been at the leading edge of climate alarmism, and his 2011 reference about the 2010 Russia heatwave… Omitting to mention that the next winters, Russia suffered some record cold waves and that other scientific papers refuted any anthropogenic climate change influence to both.
Finally, Mortillaro only provides a passing reference to the synoptic situation, just parroting the European media lines of “The culprit? Heat from northwest Africa that is making its way northward.”
The reality is quite different. It involved two high pressure anticyclonic systems, one very dynamic one at 1035hPa over the Atlantic at the eastern edge of which warm, moist oceanic air was being advected to the British Isles, western France and Portugal, each pulses of this southward descent of polar air bringing its group of powerful winds and thunderstorms, and another anticyclonic 1025hPa system slow moving covering most of eastern Europe, the western edge of which advected slowly dry warm air. France was located at the intersection of these two systems and when the eastern system was reinforced by the cold polar air descents affecting western Siberia, and extended over the entire Western Europe, the dry heat wave developed fully after a few days of mixed high humidity and high temperatures.
Already a 1033hPa new polar air descent from the Arctic Ocean is bringing colder temperatures over Moscow, Northern Europe, Germany and northern France and now Eastern Europe while in France, the area remaining affected by this heat wave has been shrinking to the size of the state of Illinois.
According to weather models, a Greenland originating polar air mass is expected to bring an end to the episode within the next four days.
Journalist Mortillaro is very prompt to compare this 2019 with the 2003 one, bringing up casualties numbers related to the 2003. But since she skirts the synoptic reality of both events, her fearmongering falls flat with those who are knowledgeable.
This media treatment is typical of parrots whose submission to a political agenda is inversely proportional to their knowledge of meteorology and climatology. They should be called out for their low professional standards.
This excellent article about a cold front in the Pacific Northwest causing record heat in San Francisco had another parallel in 2012, when global-warming alarmists were blaming global-warming for Hurricane Sandy, which caused record-high storm surges in northern New Jersey and New York City.
Most hurricanes which approach the east coast of the United States (which do not strike the Carolinas) tend to move toward the NNE, with the eye remaining offshore, and weakening as the storm goes into cold water off Nova Scotia. A hurricane with the eye a few hundred miles east of the New Jersey coast will generate winds out of the north or northeast along the shore. Storm surges are relatively small, because a wind out of the northeast does not have much “fetch” (distance of open water) because the ocean east of New Jersey is sheltered by Long Island and the southern coast of New England out to Cape Cod.
Hurricane Sandy formed near Jamaica in mid-October, and moved northward for a few days, but there was an exceptionally COLD anticyclone over the North Atlantic (between Nova Scotia and southern Greenland) in late October 2012. Easterly winds around the south side of this anticyclone steered the eye of Sandy westward into the Jersey shore near Atlantic City, and the winds to the north of the eye were out of the east and southeast, with a long “fetch” of open ocean which built up a strong storm surge which piled water up into Raritan Bay and the Hudson River, and caused massive flooding in New York City.
But is a mistake to blame “global warming” for the damage caused by Sandy. Without the COLD anticyclone over the North Atlantic, the eye of Sandy would have tracked NNE up to Nova Scotia, and New Jersey would have experienced a minor 2-3 ft storm surge typical of a “nor’easter”. As further proof that Sandy was a product of abnormally cold air, most of West Virginia received over two feet of snow from Sandy–in October!
Jim,
The EPA heat wave index was the subject of commentary in Tony Heller and Dr.Jennifer Marohassy’s article,
“It was hot in the USA- in the 1930s”, published in “ Climate Change: The Facts 2017.”
The EPA graph was shown there together with a similar graph from the NOAA GHCN daily temperature record 2016, indicating also that the peak for the percentage of days over 35C occurred in the mid 1930s.
The authors state –
“ During the 1930s, about 7% of the daily maximum temperature readings were over 35 degrees Celsius, but since 1960 that number is less than 5%.”
In addition they draw attention to Hansen et al (1999), where they say a chart appears showing 0.5 degrees C cooling in the US from the mid 1930s through to the late 1990s- with 1934 more than 0.5 C warmer than in 1998.
The Hansen article included the following comment-
“ Empirical evidence does not lend much support to the notion that climate is headed precipitately towards more extreme heat and drought….
… in the US there has been little temperature change in the past 50 years, the time of rapidly increasing greenhouse gases- in fact, there was a slight cooling throughout much of the country.”
Jim, is the recent record heat across Europe also explained by this phenomenon?
In reply to Roger Taguchi who posted June 27 at 5;14 p.m.
First about the heat capacity of gases. You explain why the heat capacity of water vapor is higher than the heat capacity of nitrogen, but why is the heat capacity of CO2 (linear non-polar molecules) higher than that of H2O? However, in relation to the problem under discussion, the point is not the explanation of heat capacity on the basis of molecular physics.
The bottom line is that the heat capacity theory does not need the hypothesis of the greenhouse effect to explain heat absorption by the atmosphere. Heat is absorbed by all gases, while their heat capacities, despite the differences, are still of the same order of magnitude. Therefore, the contribution of various components to the total heat capacity of the atmosphere is determined mainly by their concentration. And from this it follows that only water vapor makes a small contribution , for the remaining “greenhouse gases” these contributions are less than the measurement error.
With regard to the transfer of energy from CO2 to oxygen and nitrogen, then I simply comment on your statement in the post of 11:45 a.m. : “Most of the energy absorbed by CO2 is transferred via inelastic collisions to non-radiating N2 and O2 molecules that outnumber CO2 by 2500:1”. I think that if pure nitrogen can receive heat from an external source, then it also receives it in the presence of other substances. There is no evidence that the heat capacity of a mixture of gases may exceed the value calculated in the assumption of the molar additivity of this property.
A lot of comments about CO2 and IR absorption and radiation. I keep coming back to one absolute truth. Heat transport in the troposphere is controlled by convection. Look up the US standard atmosphere that represents the average conditions used for design and specifications for aircraft and other practical aeronautical purposes. The wet and dry adiabatic equations give you the temperature profile up to the tropopause. The arguments about IR radiation really only become important at the tropopause and above.
The arguments about IR in the troposphere should be questioning how does CO2 affect convection. The atmosphere has been in a robust dynamic equilibrium for billions of years. There have been scary ice ages and benign warm periods but its hard to move an equilibrium state. My own experiment in a five foot tube with water evaporation from a halogen light and condensation at an ice bath showed only a five minute temperature change at the bottom when half the air was replaced with CO2. After five minutes the temperature at the bottom went back to the same equilibrium temperature that was established before change the atmosphere to half CO2.
I suspect that there has been a small change in the average height of the tropopause as CO2 has gone up but despair at the thought of how to measure it given the weather noise.
I’ve been pointing that out for years.