Climate change, yes, but likely not what you’d expect

I have never written on anything that has sparked as much controversy as climate change.

Let’s be clear: Natural factors or forcers (not a typo) alter the world’s climate and microclimates – it’s a known fact. Volcanic eruptions, for one, can be – and have at times been – a huge influencer with respect to such changes. Where differences of opinion most often arise it seems is over the human contribution, not only to climate, but weather as well as temperature changes, either done in a direct or indirect way. We possess that capability: I can assure you.

Perhaps the most pointed example of all is the recent lack of sustained, widespread San Joaquin Valley (California) based pea-soup-thick tule fog, a meteorologic condition that was so prominent a feature in the area – sometimes lasting for months at a time – and interspersed, of course, with periods of rain and sun, during the 1970s, ‘80s and ‘90s; at least, that’s my recollection. In California’s central interior region, the occurrence of such widespread and lasting tule fog has tapered off quite a bit in the time since, observable for sure this change is, and in the central and north Valley portions, especially.

Now ask yourself why that is. Conventional, customary thinking, would have it that this has everything to do with global warming. The question is: Does it?

So, in a University of California, Berkeley (“Cal”) Apr. 10, 2019 press release it was revealed: (in the valley) “[o]xides of nitrogen (NOx) react with ammonia to form ammonium nitrate particles, which help trigger water vapor to condense into small fog droplets. Emissions of NOx have declined dramatically since the 1980s, resulting in a decrease in ammonium nitrate aerosols and fog.

“‘In order to get fog to form, not only do you need the temperature to go down, but there has to be some sort of seed for water to condense around, similar to how you would have a cloud seed in the atmosphere’,” then UC Berkeley environmental science, policy and management graduate student Ellyn Gray said. Gray, incidentally, was lead author on a UC Berkeley centered investigation researching the connection between Valley air pollution and fog formation during times of the year when conditions in California’s San Joaquin Valley are conducive to fog’s formation, that is typically the case when the exact ingredients necessary for fog to form are present. This is as I understand it. The study in question was published in The Journal of Geophysical Research: Atmospheres. “‘When we looked at the long-term trends, we found a strong correlation between the trend in fog frequency and the trend in air pollutant emissions.’

“The link between air pollution and fog also explains why southern parts of the valley — where higher temperatures should suppress the formation of fog — actually have a higher occurrence of fog than northern parts of the valley,” as expressed by Kara Manke in “Falling levels of air pollution drove decline in California’s tule fog,” the title of the Apr. 10, 2019 Cal press release in question.

Relatively few people are probably even aware of this, unfortunately. I hope that more Californians will get in the know with publication of this information.

A (California) rain, air-quality-improvement connection?

In other news, It is no secret and not lost on Californians how much rain the state has received since Oct. 1, 2022, the beginning of the current rainfall season. Fresno County had so far received 17.09 inches, well above what is considered to be normal for this time of the year. Fresno County’s average liquid precipitation amount in years with normal rain totals is 11.5 inches.

That said, it is important to note that the amounts of rain accumulating on the valley floor received this year to date, in no way makes up for the liquid-precipitation shortfalls that the Valley has sustained for years. Even though water restrictions have been eased or completely lifted in state, depending upon location, the drought in the western U.S. is still very much alive and well. So it still behooves state water users to be mindful of water usage if not taking extra care in conserving this precious resource.

In the plus column, meanwhile, are air quality conditions up and down the state. For much of the winter season and so far into spring, air quality conditions have been favorable. It will be interesting to see when all is said and done rainfall-wise, how the state has fared air-quality-wise. My expectation is for many areas of the state known for having poor air quality – which can be quite pronounced during the cold-weather months – what with the amounts of rain received during this time, to have more favorable air quality numbers. What I am happy to report is that in Fresno County, at least, there have been many days with good air quality recorded, this based on what I’ve seen and heard in local television news and/or weather reports.

News flash: Californians can expect more rain and snow in the mountains to head this way.

Last edited on Apr. 27, 2023 at 7:48 a.m. Pacific Daylight Time.

⁃ Alan Kandel

Copyrighted material.

Corresponding, connected home-page-entry image: Jeff Schmaltz, NASA