SoCal Climate Questioned
From Issue: Volume XXI - Number 13
By Kirt Ramirez
As we enter July – and as June gloom lessens – the coast of Southern California will once again enjoy the summer period of cold ocean air, warm sun and blue skies while other parts of the state and country sizzle.
SOCAL shoreline looking west.
By Kirt Ramirez
While most of the U.S. gets warm or hot, the western shorelines of Washington, Oregon and California stay mild during summertime. Weather maps displaying summer temperatures for the U.S. typically show the west coast as being the coolest part of the entire country.
Places that otherwise get cold in the winter like New York, Boston, Washington D.C., Minneapolis and Billings Montana regularly get hotter than coastal California during the summer months – not to mention muggy.
Weather reports even show the eastern parts of Canada getting hotter than the coast of Southern California this time of the year.
Of course SoCal’s inland areas and deserts get hot in the summer, but this article focuses on the beaches and coast.
This is the third consecutive June that the Beachcomber has tackled SoCal climate questions and related topics.
In the June 17, 2011 article “May Gray Turns to June Gloom,” Long Beach City College Geography Instructor, Douglas Fetters, explained that the coast’s cool climate results from the cold California Current.
This ocean current starts near British Columbia and comes out of a larger Alaskan system of frigid, arctic waters and flows alongside the western U.S. into Southern California. It keeps the beaches and coastal areas moderately cold and is the reason surfers wear wet suits.
In that issue Fetters explained what causes June gloom. The U.S. National Oceanic and Atmospheric Administration (NOAA) and others were referenced as well.
The following year, June 29, 2012, the article “SoCal Weather Myths Debunked” addressed common misconceptions many – especially tourists – have about Southern California.
Fetters returned and discussed the Mediterranean climate and other geography facts. NOAA and books also were consulted. Jutta Burger, Ph.D., co-director, science and stewardship for the Irvine Ranch Conservancy, explained that palm trees are not native to the California coast.
And Long Beach’s first palm tree was planted in 1884 by Mrs. O.M. Healy, an early resident, according to documentation at the Historical Society of Long Beach.
These articles are archived at www.longbeachcomber.com.
Meanwhile, it rains in other parts of the country and world during the summer – but not here. Why is this?
Fetters comes back to answer this year’s climate question.
“During the SoCal summer months (June through August), the North Pacific High pressure atmospheric cell that fluctuates over the Pacific between roughly 30° – 40°N latitude and 140° – 150°W longitude, increases in intensity and size. More often than not, it expands to such size and scope that it acts as an atmospheric barrier that blocks and deflects any approaching Pacific storms bound for SoCal far to the north.
“In contrast, during the winter months the opposite occurs and its size shrinks to the point where it’s located much farther south toward the equator and will not deflect Pacific storms northward. Therefore, Pacific storms have a direct pathway to Southern California during the winter.”
This explains why it is dry and not humid here during the summer and cold and wet during the winter.
The climate section of the book Introduction to the Plant Life of Southern California – Coast to Foothills – elaborates:
“California represents one of only five small regions of the world that possess a Mediterranean climate, which is characterized by mild, wet winters and dry summers. The other locations are in central Chile, the Mediterranean Basin of southern Europe and northern Africa, the Cape Region of South Africa, and Southwestern and South Australia.
“These regions with this highly unusual climate account for only a tiny portion of the world’s land area and occur only on the western margins of continental landmasses between about 30 and 40 degrees latitude. Subtropical high-pressure centers shield these areas from summer storms.”
Various shrubs and native grasses turn brown for the summer and then turn green again later in the rainy season.
Jenn Starnes, communications manager for the Irvine Ranch Conservancy, said Mediterranean climate zones occur on less than two percent of the earth’s surface.
“Rather than going through typical winter, spring, summer, fall seasons, Mediterranean climate zones are characterized by warm, dry summers and cold, wet winters. Generally, native plants adapt to this cycle, beginning regrowth in winter and turning dormant in the summer. The dormancy usually results in the plants conserving resources, turning brown or gold during the summer.”
Starnes added, “Many locally-native plants are evergreen, such as the coast live oak and Toyon. While these may have slight color changes during the seasons, they are generally unaffected during the year.”
The foliage aspect was discussed in the Beachcomber’s Nov. 30, 2012 article “Colder weather is here but most trees stay green,” also archived online.