Life is Grand in Palos Verdes, USA By William Lama Ph.D.
Life is Grand in Palos Verdes, USA
By William Lama Ph.D.
Once in a while I fret about the cost of living in California. Then I go outside, smell the flowers, feel the cool ocean breezes and calm down. We all know folks who have emigrated to Colorado, Florida, Texas, even Wyoming, for heaven’s sakes. But there is nowhere else you can find the combination of natural beauty and weather that we enjoy in Palos Verdes, IMHO.
If I’m asked to rank the reasons why I love it here, the climate would top the list. As I write this Halloween is just around the corner and the day is sunny and warm. Couples walking with dogs and kids are going up and down Via Campesina past our house, having a grand old time, in spite of the Coronavirus. What’s not to love?
But it’s not just living in Palos Verdes that is grand. Life is good on Earth because of three primary factors: (1) location, (2) atmosphere and (3) timing. Let’s examine these three aspects from a global and historical framework.
Location
The life-giving climate that we enjoy is due to location, location, location, just like all real estate.
On the cosmic scale we live in the Milky Way galaxy. Most of the 100 billion stars in the Milky Way occupy a massive circular disk (2,000 light years thick) within a series of spiral arms. Our solar system is roughly 26,000 light years from the black hole at the center of the galaxy. (A light year is the distance light travels in a year, roughly 6 trillion miles)
The sun rotates around the galactic center at a constant speed (514,000 mph) making a complete circuit in 250 million years. At the same time the sun oscillates through the central plane of the disk with a period of about 35 million years.
You might ask what all that has to do with conditions on Earth. Well, quite a bit. For example, every time the sun passes through the plane of the disk it can redirect the motion of a massive speeding comet that ultimately may hit the Earth. From Earth impact data it is known that a massive comet hits the Earth every 30-35 million years. Coincidence?
Sixty-six million years ago, a comet the size of Palos Verdes travelling at 40,000 mph hit the Earth. The collision produced the most powerful earthquake of all time, with the energy of a hydrogen bomb, heating the atmosphere and killing the dinosaurs. Of course that event made possible the rise of the mammals, without which we would not have evolved to ponder the perplexities of the cosmos. (Lisa Randall, Dark Matter and the Dinosaurs)
Closer to home, we live on the 3rd rock from the Sun.
Our location in the Solar System is magical, like living in Palos Verdes. The following table compares Earth to our nearest neighbors, Venus and Mars.
The average sunlight (irradiance, averaged over the globe and over time) falling on Earth is 1366 watts per square meter = 1 in the table. Venus is closer to the Sun and the irradiance on Venus is roughly double Earth’s dose. By contrast Mars is farther from the Sun and its mean irradiance is just 44% of Earth’s.
Atmosphere
All three planets have atmospheres but both Venus and Mars are bathed in Carbon Dioxide (96%) while the Earth atmosphere is mostly Nitrogen and Oxygen, with only 0.04% Carbon Dioxide. The result is that Venus is too hot (460 C) and Mars is too cold (-140 C), while Earth is just about right (15 C). “Habitability” of a planet is the ability to support surface water. NASA estimates that in the Milky Way there may be 300 million habitable planets (0.3%). Earth is a lucky one.
The Earth’s global temperature is a grand average of temperatures measured all around the world and over the year. That average is presently 15 degrees centigrade (+/- 1 C). In simplest terms the Earth temperature is obtained via an energy balance between the solar irradiance that warms, illuminates and nourishes the Earth, and the longer wavelength radiation that is reflected back into space. The most important realization is that without the atmosphere the Earth temperature would be -1 C, that is frozen. Also the clouds increase the reflectivity and reduce Earth temperature to -18 C, too cold for life.
What saves us is the Greenhouse Effect that raises the Earth temperature by 33 degrees making life on Earth possible. The short wavelength sunlight that is not reflected by clouds or snow warms the Earth. The Earth emits long wavelength IR radiation thereby cooling off.
Greenhouse Effect, Wikipedia
But some of the IR is absorbed by molecules in the atmosphere thereby retaining some of the heat; ie the Greenhouse Effect. The major Greenhouse gas is water vapor accounting for 30 degrees of warming. The second is Carbon Dioxide (3 degrees of warming). Note that a 3% decrease in cloud cover would increase the Earth temperature by 1 degree, accounting for all the warming of the 20th century.
Timing
We are very fortunate that the average Earth temperature has been around 15 C for the last 9,000 years, during the Holocene interglacial period.
The figure records the change in temperature relative to the current 15 C. The horizontal axis is the time before present. Note that during the period 10-110 thousand years ago it was icy cold. At the last glacial maximum the average Earth temperature was only 15 C – 9 C = 6 C. That recent Ice Age cycle lasted for about 100,000 years following the last interglacial (the Eemian) when it was warmer than it is now. Long term we know that we are headed for the next cycle of the Ice Age that has gripped the Earth for the last 30 million years. The blessed Holocene is nearly finished and we are in for 100,000 years of cold. Imagine what property in Palos Verdes will be worth then.
Shorter term the mild warming will likely continue. On the other hand solar activity (sunspots) will have the effect of increasing cloud cover and lowering temperature. It’s possible that another Little Ice Age (1300-1850) - when life was “nasty, brutish and short”- could occur.
As I told my physical poets (Nov. 2020 issue of PV Pulse) make hay while the sun shines, in Palos Verdes, USA.
Dr. William Lama has a PhD in physics from the University of Rochester. Taught physics in college and worked at Xerox as a principle scientist and engineering manager. Upon retiring, joined the PVIC docents; served on the board of the RPV Council of Home Owners Associations; served as a PV Library trustee for eight years; served on the PV school district Measure M oversight committee; was president of the Malaga Cove Homeowner's Association. Writes about science, technology and politics, mostly for his friends.
email: wlama@outlook.com