A city of sun, wrapped in gloom

THIS IS THE “Land of Sunshine”? You don’t need a weatherman to know it isn’t so. Veteran Angelenos (that is, anyone here at least a year) know the disappointment of waking to skies as gray as freshly poured concrete, of noons that appear filtered through the dome of a dirty milk glass and of afternoons that play out in miserable dullness until, like a cruel gift, sunset roars through a slit on the western horizon in colors of magenta and gold.

The climate people say we have only two seasons in Los Angeles: wet and dry. But we know many more seasons of light. Right now, it’s the season of gray light, the season of the newcomer’s first regrets.

Spring and early summer in Los Angeles, according to the National Oceanic and Atmospheric Administration, deliver an average of just 11 clear days in May and 14 in June. The definitions of “clear” and “cloudy” are subjective, but on even the partly cloudy days, the daylight hours are at least half obscured.

Just how gray depends on where you live. At LAX, June usually yields no more than nine perfectly clear days. In coastal cities from Malibu to Seal Beach, the gloom can linger all day, putting off the start of their summer until after the Fourth of July.

The gray season is made in the Pacific Ocean. Cold currents rise close to shore; a persistent high-pressure zone farther out channels warmer air eastward, and the springtime vortex called the Catalina Eddy fabricates fog from the interaction of cool water and warm air, pushing it on shore when the air of inland valleys rises in the heat of midday. Television weathercasters call the visible result “the marine layer,” although what they’re really taking about is fog.

It ambles over the beaches after midnight, flows in wide streams up the former bed of the Los Angeles River through the western half of the city and takes general possession of the basin under the same inversion layer that brews smog. On good days, the sun eventually burns down through half a mile of gray clouds and illuminates, at last, a city that seems to have been forgotten by sunlight and color.

It could be worse. Tourists before the mid-20th century often complained that a dull haze shrouded the charms of what had been advertised as a perpetually sunlit Mediterranean city. William Faulkner called the lighting effect a “treacherous unbrightness.” The incidence of thick fog, however, has been reduced by about half, based on measurements at LAX and the Long Beach Airport.

The reasons are complicated. The basin is much drier than it once was, when seasonal wetlands covered all the low ground of western Los Angeles. “Advection fog” results when warm air crosses cool ground (in the same way the marine layer is created over water). A drier basin produces less fog. And built-up Los Angeles is a typical urban “heat island” that pumps out enough warmth to disrupt at least some of the onshore flow. That air is cleaner too, thanks to the relative success of pollution controls that have cut particulates and the resulting condensation that makes both haze and fog.

But our season of gloom won’t get any shorter, at least not until the cycles of El Ninos and La Ninas -- warm and cold Pacific currents -- line up the way they did before 1998. According to Caltech oceanographer William Patzert and his colleagues, Steve LaDochy and Jeff Brown of Cal State L.A., the 1980s and 1990s were years of truly “endless summer” in Los Angeles, marked by a succession of bright days and brilliant nights.

That charmed pattern is broken. The oscillation from warmer, wetter, less hazy winters and springs to seasons that are cooler, drier and more likely to spawn gray days takes about 25 years. We have a long time to wait for more light in June. But there’s always nearby Yuma, Ariz., with nearly 250 clear days a year.

This week, most of the city won’t be sunny because of forces that have nothing to do with you or me or why we fell for a sales pitch that skipped over a few of the climatological details. You could look on the bright side -- the gray skies of spring are part of the natural air conditioning that keeps much of the basin cooler in summer.

It would be better if we dropped the blue-sky pretense anyway. The gray skies, in their ever-returning cycle, have been faithful in their baleful way. This is the place we’ve come to, as much mediocre gray in its season as it is superlative brilliance. The whole of the experience of Los Angeles is what we need to embrace to become truly native to this place.