LOS ANGELES 2025, MOTHER OF ALL WILD FIRES
A fire prone region, a drought, La Nina winter weather,, a cold air outbreak, a teenager’s New Years Eve “pot party” in the woods, illegal fireworks, a small fire erupts, duly snuffed out by the LA FD, and a week later, fierce 90 mph Sant’Anna winds reignite the undetected cinders. These events all horribly compounded and extended by WOKE DEI ideology, misplaced priorities, one party rule, local political hubris, human frailty, poor planning, incompetent and missing bureaucrats and human stupidity.
The Los Angeles Pacific Palisades fire, has become the penultimate (we hope) disaster of the Biden, disaster-plagued administration. This terrible ecologic and human tragedy is a result of governmental failure resulting from misplaced priorities, one party rule, self righteousness, and stupidity coupled with predictable natural weather, geography and native floristic phenomena which culminated in a cataclysmic firestorm without historic precedent.
The apocalyptic conflagrations in Los Angeles appears to have started in the Pacific Palisades section of that city on January 7, 2025. An extensive investigation by the WAPO newspaper appears to indite the activities of a New Year’s Eve teenage “pot party” in the bone dry woods of the Pacific Palisades section of Los Angeles, where fireworks may have ignited La Nina weather dry forest litter. That fire was reported and duly responded to by the LA FD. They reported an area of about 3-8acres in flames. They effectively contained and extinguished that small fire on Jan 1, 2025.
A week later, as a result of winter La Nina weather patterns, i.e. a cold dry outbreak of air which settled into the Great Basin and generated an unseasonably powerful Sant’Anna wind. The high winds impacted the region on January 7, 2025 causing the week-earlier Palisades New Year’s Eve fire-site to reignite.
Reigniting is a serious problem in very windy locations. (Fires can smolder under soil litter, dead leaves, or in soil humus layer (organic rich top layer of soil), and in dry punky wood for weeks). The LA FD does not maintain patrols on past fire sites. But a week later, the winds were so severe (60-90 mph) smoldering cinders came to life, flames sprouted and fire spread so rapidly that containment with the available man power and mechanical assets were fruitless and the Pacific Palisades fire spread rapidly.
The result: Los Angeles’ strikingly intense, wild fires burned 40,000 acres to cinders, 12,000 frame structures were totally consumed by extremely hot fires leaving only twisted metal, concrete and brick structures cracked and collapsed where homes, churches, stores formerly stood, 150,000 people were evacuated, and sadly 25 people lost their lives in the conflagration.
Wells Fargo estimated damages and economic loss at about or as much as$130 billion or as little as $60 billion.
Three fires have plagued the City since January 7, 2025. The first and largest is the Pacific Palisades fire on the west end of the LA County. Fifteen miles to the NE is the Eaton Fire. Then to northwest near Pasadena is the smaller Hurst Fire north of San Fernando which has consumed 14000 acres and burned 7,000 structures.
But what makes the forested and natural regions of southern California, so “fire prone”.
The climate of Los Angeles and Southern California characterized by hot dry summers and mild wet winters is classed as “Mediterranean”. (Though during La Nina weather, winters in thjs region are colder and dry.) The natural vegetation adapted to the Mediterranean climate is known as “chaparral” a biome comprised of plants adapted to dry, hot weather and low-moisture soils. “Chaparral vegetation is characterized by low growing shrubs with leathery, drought-resistant waxy leaves that often form near-impenetrable thickets.”
The common plants of California chaparral are manzanita, acacia, juniper, and shrub-live-oaks. Juniper and oaks are well known and occur widely, but manzanita and acacia occur more commonly in the west and Mexico. Manzanita is an evergreen bush-or low tree of the Heath Family with small red edible fruit with twisted red-barked branches. The bark readily peels away to form loose red strips and burns easily. “Manzanita” in Spanish means “little apple”. Acacia is a low growing shrub or small tree with compound leaves and is a member of the pea (Fabacea) family. It has bean-like fruits which are edible and it branches are well supplied with thorns.
The chaparral species form low dense thickets often associated with other species with similar adaptations to heat, drought and low soil moisture. This pattern of growth in low growing closely spaced thickets is itself an adaptation to a climate in which the conservation of plant and soil moisture is critical to survival.
These drought adaptations, however, also make this biome highly susceptible to wild fires. In fact archeological studies and historic accounts indicate that wild fires were common occurrences in the distant past prior to historic human occupation.
In addition to their waxy leaves and often dry peeling bark chaparral’s growth pattern, close to the ground in dense thickets, increase susceptibility to wild fires. Such chaparral thickets flare up in towering flames in seconds as violent hot winds carrying flying embers descends, ignites finely divided fuels like waxy leaves and fine branches which explode into towering flames which generate heated air that rises carrying more embers burning leaves and branches which then carry the fire to a new area.
When chaparral achieves ignition temperature—their finely divided character (leaves, thin branches and fine twigs) with increased surface area in contact with air in the thicket can ignite, instantly combining the tinder like fuel with the surrounding oxygen in the air to almost instantly oxidize the mass of wood and leaves into heat and gases to generate an almost explosive flaming inferno. See examples of “dust explosions”. Chaparral fires are intensely hot. The heat generated can ignite other surfaces and materials near by, structures, homes automobiles, which then add to the exponentially increasing conflagration.
For this reason, so called “controlled burns” to reduce fuel levels may not be practical in chaparral biome dominated areas. Though in more typical forests at higher elevations where controlled ground fires can safely burn downed tree limbs and understory vegetation, such policies can help reduce incidence of very hot fires.
What about the strong winds? The dry air? The Sant’Anna Winds?
These wild fire-generating meteorological phenomena are related to weather, climate and geography.
Los Angeles is located on the west coast, parts of which are at or near sea level. But as one travels east, the topography becomes mountainous rising over a series of roughly north south mountain ranges such as the Coast Ranges, Panamint Range and a southern extension of the Sierra Nevada. (While the San Gabriel Mts are part of the “transverse range” which trend east west).
Continuing east over these coastal ranges and the higher Sierra Nevada one enters into a physigraphic province known as the Great Basin (GB), the base of which has an average elevation of about 4000 feet above sea level. The GB is surrounded by other high mountain ranges (it is an actual enclosed “basin”).
The only outlet for cold air trapped in the GB is in the southwest, where air can descend from its 4000 foot base level, flow through and over the Costal Ranges and into the Los Angeles physiographic basin.
Since the flowing air is forced to channel through narrow valleys surrounding Los Angeles where, (based on the Bernoulli principle,) aid flow compressed into a narrow channel speeds up and can reach hurricane force levels (74 mph) and higher (some have been reported at 90 mph)
In January* winter weather patterns often carry very cold masses of dry air into the Great Basin. Typical January average low temperatures hover around 15F, with daily highs at about 39F. These cold air masses are also low in Relative Humidity which is a measure of how close air is to saturation of water vapor. RH in January varies but thpical cold dry air has RH values often at around 66% .
*It is notable that weather of January2025 was affected by la Nina “weather” which tends to bring colder drier weather outbreaks to the Great Basin in Nevada.
In this process of air flowing from higher regions to lower levels air is compressed by the increase in overlying layers. Compression causes air to heat up according to standard gas laws (PV=nRT). (Recall how a bicycle pump heats up as one pumps (compresses) air into a bicycle tire.) As a result, for each 1000 foot descent, air heats up by about 3.5deg F. Significantly, as air heats up its RH (humidity) decreases. Thus, GB air which starts out as a cold low humidity air mass to begin with, dries out significantly as it passes over interceding mountain ranges then descends into the LA basin.
A mass of cold GB air descending into the Los Angeles Basin would have passed over several mountain ranges, losing moisture and heating as it descends. Air at a 39F day-time GB temperature, descending from 4000 feet to sea level, would heat up by (3.5x4= 14F) 14 F degrees, arriving at the LA Basin 14 degrees warmer or (39F+14F =53F) at 53 F but its RH of 66% would have been drastically reduced .
On its passage this now warmer dry air is forced to flow through narrow steep sided east west valleys and canyons where wind speeds increase (Bernoulli Effect) at times to hurricane force levels.
All that is needed under these circumstances is a spark from a toppled power-line, a careless smoker tossing a lit cigarette butt, or a still smoldering week old fire, the result of inebriated teenager’s “year-end” celebrations coaxed back to life by powerful winds!
It’s notable that on January 22, 2025, a second outbreak of powerful Sant’Anna winds helped spread Hughes Fire burning near Castaic Lake north of Santa Clarita which started as a five acre blaze which expanded to 5,000 acres in only a little more than two hours.
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