Anchor ads are not supported on this page.

4S Ranch Allied Gardens Alpine Baja Balboa Park Bankers Hill Barrio Logan Bay Ho Bay Park Black Mountain Ranch Blossom Valley Bonita Bonsall Borrego Springs Boulevard Campo Cardiff-by-the-Sea Carlsbad Carmel Mountain Carmel Valley Chollas View Chula Vista City College City Heights Clairemont College Area Coronado CSU San Marcos Cuyamaca College Del Cerro Del Mar Descanso Downtown San Diego Eastlake East Village El Cajon Emerald Hills Encanto Encinitas Escondido Fallbrook Fletcher Hills Golden Hill Grant Hill Grantville Grossmont College Guatay Harbor Island Hillcrest Imperial Beach Imperial Valley Jacumba Jamacha-Lomita Jamul Julian Kearny Mesa Kensington La Jolla Lakeside La Mesa Lemon Grove Leucadia Liberty Station Lincoln Acres Lincoln Park Linda Vista Little Italy Logan Heights Mesa College Midway District MiraCosta College Miramar Miramar College Mira Mesa Mission Beach Mission Hills Mission Valley Mountain View Mount Hope Mount Laguna National City Nestor Normal Heights North Park Oak Park Ocean Beach Oceanside Old Town Otay Mesa Pacific Beach Pala Palomar College Palomar Mountain Paradise Hills Pauma Valley Pine Valley Point Loma Point Loma Nazarene Potrero Poway Rainbow Ramona Rancho Bernardo Rancho Penasquitos Rancho San Diego Rancho Santa Fe Rolando San Carlos San Marcos San Onofre Santa Ysabel Santee San Ysidro Scripps Ranch SDSU Serra Mesa Shelltown Shelter Island Sherman Heights Skyline Solana Beach Sorrento Valley Southcrest South Park Southwestern College Spring Valley Stockton Talmadge Temecula Tierrasanta Tijuana UCSD University City University Heights USD Valencia Park Valley Center Vista Warner Springs

San Diego's Green Flash Phenomenon

Mirage effects over the ocean can cause the setting sun to split into two images, with the upper image shrinking to a green point.
Mirage effects over the ocean can cause the setting sun to split into two images, with the upper image shrinking to a green point.

Crystal-clear skies are visiting us again, as Santa Ana winds swoop down intermittently from the northeast, as cold winds blow from the north, or as high pressure invades the county and lingers here for a day or two. This is the best time to try for a sighting of the famed “green flash” of the setting or rising sun. Pacific Beach’s Green Flash Restaurant and Vista’s Green Flash Brewing Company pay homage to this elusive, non-illusory optical effect and its renown among San Diego skywatchers.

The flash itself is sometimes no more than a fleeting glimmer of emerald green on the horizon when only the barest hint of the sun’s upper rim is exposed to view. A complex optical chemistry involving refraction, dispersion, and scattering of sunlight through the atmosphere explains how the various colors of the low-angle sun split into slightly different paths so that observers on the ground see the color green on top. Clouds and any kind of light-absorbing dust or haze tend to mask the phenomenon completely. Beach residents don’t see the green flash as much at sunset as they think they should because there’s often too much fog, haze, or smog above the ocean surface.

Sponsored
Sponsored

On occasion, the mirage-like effects of temperature inversions (warmer air overlying cooler air) over the ocean can cause the setting sun to apparently split into two images, with the upper image shrinking to a green point or line before the lower image disappears on the horizon. That’s another kind of green flash. The effect can appear dramatic when seen in binoculars, provided the observer is situated at the just the right altitude above the ocean.

Sunrise actually offers more opportunity, especially in late fall and winter when the air to the east is dry and clear. Just look east at around 6:35 a.m. (currently) and try to catch the sun clearing a flat, level segment of the mountain profile. The first glimmer of bright light you see may be colored green. Very quickly that spot turns yellow or white, and soon thereafter the gathering sunlight becomes too bright to look at safely or comfortably. I’ve seen green flashes at sunrise over far eastern horizons of Arizona and Sonora, Mexico, from the 6000-foot summits of the Laguna Mountains, east of San Diego.

You can also see the green flash over artificial horizons (as opposed to mountain or ocean horizons) — as long as the setting or rising sun is very low in the sky. On one occasion, while driving westbound on the Martin Luther King Freeway near 25th Street just a few minutes before sunset, I witnessed a quarter-second-long green flash over the flat roof of the Meridian condominium tower downtown.

The latest copy of the Reader

Here's something you might be interested in.
Submit a free classified
or view all
Previous article

Ray Kroc and Hunter S. Thompson had nothing on Trump

Reader’s Walter Mencken carries the story from 2016 forward
Next Article

My brother gave up the Reader crossword

Encinitas cliff collapse victims not so virtuous
Mirage effects over the ocean can cause the setting sun to split into two images, with the upper image shrinking to a green point.
Mirage effects over the ocean can cause the setting sun to split into two images, with the upper image shrinking to a green point.

Crystal-clear skies are visiting us again, as Santa Ana winds swoop down intermittently from the northeast, as cold winds blow from the north, or as high pressure invades the county and lingers here for a day or two. This is the best time to try for a sighting of the famed “green flash” of the setting or rising sun. Pacific Beach’s Green Flash Restaurant and Vista’s Green Flash Brewing Company pay homage to this elusive, non-illusory optical effect and its renown among San Diego skywatchers.

The flash itself is sometimes no more than a fleeting glimmer of emerald green on the horizon when only the barest hint of the sun’s upper rim is exposed to view. A complex optical chemistry involving refraction, dispersion, and scattering of sunlight through the atmosphere explains how the various colors of the low-angle sun split into slightly different paths so that observers on the ground see the color green on top. Clouds and any kind of light-absorbing dust or haze tend to mask the phenomenon completely. Beach residents don’t see the green flash as much at sunset as they think they should because there’s often too much fog, haze, or smog above the ocean surface.

Sponsored
Sponsored

On occasion, the mirage-like effects of temperature inversions (warmer air overlying cooler air) over the ocean can cause the setting sun to apparently split into two images, with the upper image shrinking to a green point or line before the lower image disappears on the horizon. That’s another kind of green flash. The effect can appear dramatic when seen in binoculars, provided the observer is situated at the just the right altitude above the ocean.

Sunrise actually offers more opportunity, especially in late fall and winter when the air to the east is dry and clear. Just look east at around 6:35 a.m. (currently) and try to catch the sun clearing a flat, level segment of the mountain profile. The first glimmer of bright light you see may be colored green. Very quickly that spot turns yellow or white, and soon thereafter the gathering sunlight becomes too bright to look at safely or comfortably. I’ve seen green flashes at sunrise over far eastern horizons of Arizona and Sonora, Mexico, from the 6000-foot summits of the Laguna Mountains, east of San Diego.

You can also see the green flash over artificial horizons (as opposed to mountain or ocean horizons) — as long as the setting or rising sun is very low in the sky. On one occasion, while driving westbound on the Martin Luther King Freeway near 25th Street just a few minutes before sunset, I witnessed a quarter-second-long green flash over the flat roof of the Meridian condominium tower downtown.

Comments
Sponsored

The latest copy of the Reader

Here's something you might be interested in.
Submit a free classified
or view all
Previous article

Two poems for Christmas by Joseph Brodsky

Star of the Nativity and Nativity Poem
Next Article

Our lowest temps are typically in January, Tree aloes blooming for the birds

Big surf changes our shorelines
Comments
Ask a Hipster — Advice you didn't know you needed Big Screen — Movie commentary Blurt — Music's inside track Booze News — San Diego spirits Classical Music — Immortal beauty Classifieds — Free and easy Cover Stories — Front-page features Drinks All Around — Bartenders' drink recipes Excerpts — Literary and spiritual excerpts Feast! — Food & drink reviews Feature Stories — Local news & stories Fishing Report — What’s getting hooked from ship and shore From the Archives — Spotlight on the past Golden Dreams — Talk of the town The Gonzo Report — Making the musical scene, or at least reporting from it Letters — Our inbox Movies@Home — Local movie buffs share favorites Movie Reviews — Our critics' picks and pans Musician Interviews — Up close with local artists Neighborhood News from Stringers — Hyperlocal news News Ticker — News & politics Obermeyer — San Diego politics illustrated Outdoors — Weekly changes in flora and fauna Overheard in San Diego — Eavesdropping illustrated Poetry — The old and the new Reader Travel — Travel section built by travelers Reading — The hunt for intellectuals Roam-O-Rama — SoCal's best hiking/biking trails San Diego Beer — Inside San Diego suds SD on the QT — Almost factual news Sheep and Goats — Places of worship Special Issues — The best of Street Style — San Diego streets have style Surf Diego — Real stories from those braving the waves Theater — On stage in San Diego this week Tin Fork — Silver spoon alternative Under the Radar — Matt Potter's undercover work Unforgettable — Long-ago San Diego Unreal Estate — San Diego's priciest pads Your Week — Daily event picks
4S Ranch Allied Gardens Alpine Baja Balboa Park Bankers Hill Barrio Logan Bay Ho Bay Park Black Mountain Ranch Blossom Valley Bonita Bonsall Borrego Springs Boulevard Campo Cardiff-by-the-Sea Carlsbad Carmel Mountain Carmel Valley Chollas View Chula Vista City College City Heights Clairemont College Area Coronado CSU San Marcos Cuyamaca College Del Cerro Del Mar Descanso Downtown San Diego Eastlake East Village El Cajon Emerald Hills Encanto Encinitas Escondido Fallbrook Fletcher Hills Golden Hill Grant Hill Grantville Grossmont College Guatay Harbor Island Hillcrest Imperial Beach Imperial Valley Jacumba Jamacha-Lomita Jamul Julian Kearny Mesa Kensington La Jolla Lakeside La Mesa Lemon Grove Leucadia Liberty Station Lincoln Acres Lincoln Park Linda Vista Little Italy Logan Heights Mesa College Midway District MiraCosta College Miramar Miramar College Mira Mesa Mission Beach Mission Hills Mission Valley Mountain View Mount Hope Mount Laguna National City Nestor Normal Heights North Park Oak Park Ocean Beach Oceanside Old Town Otay Mesa Pacific Beach Pala Palomar College Palomar Mountain Paradise Hills Pauma Valley Pine Valley Point Loma Point Loma Nazarene Potrero Poway Rainbow Ramona Rancho Bernardo Rancho Penasquitos Rancho San Diego Rancho Santa Fe Rolando San Carlos San Marcos San Onofre Santa Ysabel Santee San Ysidro Scripps Ranch SDSU Serra Mesa Shelltown Shelter Island Sherman Heights Skyline Solana Beach Sorrento Valley Southcrest South Park Southwestern College Spring Valley Stockton Talmadge Temecula Tierrasanta Tijuana UCSD University City University Heights USD Valencia Park Valley Center Vista Warner Springs
Close

Anchor ads are not supported on this page.

This Week’s Reader This Week’s Reader