Wildfires in California

https://www.newsbreak.com/@c/1592092?s=01

Emerald fire rate at 20% in Laguna Beach area, officials warn 'be vigilant'

     Firefighters gained the upper hand Thursday morning after a wind-driven brush fire broke out near a multimillion-dollar gated, ocean-view residential community in the Laguna Beach area.

     But by late afternoon, the city's fire chief warned residents to "stay vigilant."

     Beginning around 4 a.m., the fire threatened the Emerald Bay community, which stretched into the hilly wilderness area west of Laguna Beach.  With strong winds, the fire engulfed 145 acres in just a few hours.

     At 5 p.m., after the evacuation order was lifted, fire officials announced they had managed to bring the blaze to that size and said it was about 20 percent contained.

     "We probably have the flames under control now," Laguna Beach Fire Chief Michael Garcia said at a news conference.  "But residents, stay vigilant... be prepared. You may get that order again."

     For many longtime residents, the fire is reminiscent of the devastating Laguna Beach fire of 1993, which ravaged the neighborhood and several other locations.

     Officials did not specify the exact location of the blaze Thursday, but Orange County Fire Chief Brian Hennessy said crews were trying to contain the blaze between the boat and the Emerald Canyon Highway on two routes.  .  Deep into the hills above Emerald Bay.

     The bushfires were the only blaze in the state on Thursday morning, so resources from other agencies could help immediately.

     With parts of California still experiencing a cold, dry winter, it was too early for the state's fires to break out in February.  Fennessey said the fires near Emerald Bay started in warm, dry conditions, which are not common in the middle of winter.

     "We no longer have fire seasons, we have fire years," he said.  "If that's any indication of what's to come - we've had a long year."

     The fire forced the evacuation of homes near Emerald Bay and Irvine Bay, closed sections of the Pacific Coast Highway and closed an elementary school.  Highways then reopened, and the order was lifted Thursday afternoon, but evacuation warnings remained in place and counties and state parks in the fire zone were closed.

     No one was injured.  There have also been no reports of any damage to the building.

     MORE: This map shows where the Emerald Fire is burning

     A helicopter drips from an early morning fire near a burning house on the hills near Emerald Bay and Irvine Bay in Laguna Beach, Thursday, Feb. 10, 2022.  (Photo by Mark Rightmeier of Orange County Chronicle/SCNG)

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     Smoke rises after sunrise along the Pacific Coast Highway as early morning fires burn on the hills above Emerald Bay and Irvine in Laguna Beach, Thursday, Feb. 10, 2022.  (Photo by Mark Rightmire of Orange County Register/SCNG)

     Ahttps://images.app.goo.gl/UjYbWv9jNGEA9Xcb9

     The Pacific Coast Highway burns on the hills above Emerald Bay and Irvine in Laguna Beach on Thursday, February 10, 2022.  (Photo by Mark Rightmire, Orange County Register/SCNG).jpgmorning fire near a burning house on the hills near Emerald Bay and Irvine Bay in Laguna Beach, Thursday, Feb. 10, 2022.  (Photo by Mark Rightmeier of Orange County Chronicle/SCNG)

https://images.app.goo.gl/LQjaUHJ12wbfUHXA9

     An early morning fire broke out in the hills above Emerald Bay and Irvine in Laguna Beach on Thursday, February 10, 2022.  (Photo by Mark Rightmire, Orange County Register/SCNG)

https://images.app.goo.gl/tpWw3riUbHNscRXn7

     Four Cal Fire aerial tankers, five helicopters and more than 75 engines had extinguished the fire as of mid-morning, OCFA Captain Paul Holiday said.

     The first call about the fire came at 4:10 a.m.  The initial reaction was strong, "several engines and a plane," Fennessey said.  At one point, firefighters "placed an engine in front of almost every home" as the fire got closer to Emerald Bay.

     The fire eventually left the house.

     "We've been lucky in this regard," Fennessey said.

     It is unclear what ignited the fire.

     Out of an abundance of caution, the Laguna Beach Unified School District announced the cancellation of classes at all district schools, school officials said.

     High winds at night were expected to be the initial concern, but Holiday said crews were able to establish fire lines around Boat Canyon and Morrow Ridge.  Crews used bulldozers to dig soil around the fire to prevent further spread.

     Holiday said he was confident the line would remain the same throughout the evening after doing so in the afternoon wind.

     He said strike teams planned to work overnight to contain any hot spots that popped up and resume operations with air support if needed.

     Both Emerald Bay and its gated community neighbor, Irvine Bay, are located in unincorporated Orange County and have some of the most expensive residential real estate in the county.  Billionaire Warren Buffett owns and sells two homes in Emerald Bay.  Irvine waterfront homes regularly top the county's most expensive sales list this year.

     Diane Mello moved into Laguna Beach in 1993, not long after the city's last fire destroyed hundreds of homes.  She immediately thought of the experience after receiving a text message about the Emerald fire at around 5.15am on Thursday.

     Merlo, 54, went outside and saw a huge grey feather on a hill across the street from her home.

     "The sky was pitch black," Mello said.  "You have to wear a mask and you can see the ashes falling from the sky."

     She and her husband packed up valuable documents such as passports and ID cards, and packed up the car.  When Melo realized Thursday's fire wasn't spreading as uncontrollably as she remembered 27 years ago, she was helping her husband spray their property.

     Realizing this, they decided to stay.

     "If it starts to go down here, we have to leave, we will leave," Merlo said, standing at the entrance to Irvine Bay and PCH as helicopters sprinkled water on the charred hills behind the community.  "You can't argue with fire."

     In 1993, the Laguna Beach Fire lasted less than a day but burned 441 homes, burned 14,000 acres and caused $528 million in damage.

     A point of contention during the fire was the lack of water available to firefighters.  Now, more than 25 years later, the city has more water to fight fires, homeowners must follow stricter guidelines, trees and vegetation must be cleared around their homes to create more defensive space, and firefighters have more  Technology.

     Still, Cal Fire has designated the city and surrounding vacant lots as a "high fire zone."

     There have been four fires in the past decade.  A fire in the lush canyon above Ruby's Diner in 2012, a power line fire in Laguna Canyon in 2015, and a fire in Aliso and Wood Canyon in June 2018 burned 200 acres of heath shrub and threatened the ridges above Laguna.  Dozens of beach houses.

     In 2019, the Laguna Beach City Council passed the first phase of a $166 million plan to protect the city from fire threats.  The Fire Safety Mitigation Plan was developed over seven months in which data was collected on trips to Paradise, the Northern California town nearly destroyed by the Camp Fire.

     Fire Department expands fuel retrofit program - done by brush-eating goats and crew.  And created a new city position for fire inspectors to oversee brush removal and provide residents with fire preparation resources.

     Power poles will be buried in areas such as Bluebird Canyon, Coastal Road and Park Avenue.  Evacuation routes have been improved by adding signage and installing signal lights that can turn green to aid evacuation.  The city has also added fire detection cameras and two helicopter refueling stations

Laguna Beach lifts evacuation orders as firefighters contain Emerald Fire

Laguna Beach lifts evacuation orders as firefighters contain Emerald FireOrange County Fire Authority/

Conclusion:Los Angeles County Fire Inspector Sean Ferguson told KCBS-TV that firefighters were quickly getting the fire under control.

    Before dawn, another fire broke out in the hills above the Orange County community of Emerald Bay near Laguna Beach, as Santa Ana gusts sent a plume of smoke across the usually picturesque coastline and out to sea.

    Hundreds of residents fled their homes before the winds subsided, and an influx of firefighters and planes slowed the Emerald blaze.  Officials said 150 acres (61 hectares) were burned, but no homes were destroyed.  The cause is under investigation.

    While firefighters appear to have prevented a repeat of the 1993 blaze that destroyed and damaged hundreds of Laguna Beach homes, it marks the second wildfire to hit California this winter, following a blaze near Big Sur in January  after a fire.

    "We no longer have fire seasons -- we have fire years," Orange County Fire Chief Brian Fennessey said at the Emerald Fire briefing.  “It’s February 10th and it should be midwinter. We’re looking forward to the 80s, 90s (26.6-32.2 degrees Celsius).”

    The storm swept the state in December, but then disappeared.  Southern California has seen a heatwave this week as high pressure in the interior of the west pushes extremely dry air toward the coast, creating Santa Ana winds that are causing warmer temperatures, loss of vegetation moisture and increased fire danger.

    For a state that has suffered massive fires in recent years, the prospect of no longer offering some protection against wildfires in the winter is ominous.

    Last year, wildfires in California burned more than 4,000 square miles (104,000 square kilometers) and destroyed more than 3,600 structures, according to preliminary data from the California Department of Forestry and Fire Protection.

    In 2020, a staggering 6,600 square miles (172,000 square kilometers) and nearly 9,250 buildings were burned.  Cal Fire's report on the 2020 fire siege states: "Since 2015, the term 'unprecedented' has been used year after year as the situation worsens and climate change actually works."

    The recovery from the December floods has stalled: More than 99 percent of California remains in drought, most of it classified as severe, the U.S. Drought Monitor reported Thursday.

    The fight against the Emerald fire was aided by the rapid arrival of a large number of firefighting resources: 75 fire trucks, 5 helicopters, 4 aerial tankers, 5 laborers and 2 bulldozers.

    Fortunately, the Emerald Fire is the only active wildfire in the state with no competition for resources, Fennessey said, noting that was not the case with the catastrophic fires in Laguna Beach in 1993.

    But he noted that with several more days of windy, dry and hot weather expected, resources could still be stretched.

    Arson investigators are at the scene of the fire, Fennessey said.  He confirmed there were wires in the area, but added that he would not speculate on the cause.

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Neural control

 

Points To Remember

Coordination : Process through which two or more organs interact and complement the functions of one another surrounding the brain.

Action potential : A sudden change in the electrical charges in the plasma

membrane of a nerve fibre.

Aqueous humour : The thin watery fluid that occupy space between lens

and cornea in eye.

Blind spot : A spot on ratina which is free from rods and cones and lack the ability for vision.

Cerebrospinal fluid : An alkaline fluid present in between inner two layer

of meninges, surrounding the brain and spinal cord.

Cerebellum : A part of hind brain that controls the balance and posture of the body.

Cochlea : A spirally coiled part of internal ear which is responsible for hearing.

Corpus callosum : A curved thick bundle of nerve fibres that joins two

cerebral hemisphere.

Depolarisation : A condition when polarity of the plasma membrane of

nerve fibre is reversed.

Endolymph : The fluid filled within membranous labyrinth. Ecustachian tube : A tube which connect ear cavity with the pharynx. Fovea : An area of highest vision on the ratina which contain only cones.

Meninges : Three sheets of covering of connective tissue wrapping the brain.

Grey Matter : This shows many convolutions which increase the amount of vital nerve tissue.

Medula oblongata : Posterior most part of the brain which is continuous with spinal cord and control respiration, heart rate,swallowing,vomiting.

Pons : Thick bundles of fibres on the ventral side of brain below cerebellum.

Foramen magnum : A big aperture in the skull posteriorly through which spinal cord emerges out.

Spinal cord : A tubular structure connected with medulla oblongata of brain and situated in the neural canal of the vertebral column, covered by meninges.

Synaptic cleft : A narrow fluid filled space which separates two membranes

of the two neurons at the synapse.

Synaptic vesicles : These are membrane bound vesicles in the axoplasm of the axon terminal and these store neurotransmitter.

Neurotransmitter : These are chemicals stored in synaptic vesicles, diffuse to reach the membrane of next neuron for its stimulation.

Synapse : A physiological junction between axon of one neuron and dendrite

of next neuron.

CNS—Central neural system PNS—Peripheral neural system ANS—Autonomic neural system

Neural System

Central neural System    Peripheral neural System

Brain	Spinal cord	Cranial nerve	Spinal nerve
		12 pairs	31 pairs

Nerve fibres of PNS

Afferent fibres Tansmit impulse    Efferent fibres Transmit impulse

from Tissue/organ to CNS        from CNS to Peripherel tissue/organ Division of PNS

Somatic neural System    Automatic neural system Transmit

Relays impulse from CNS    impulse from CNS to involuntary to Skeletal muscle    Organ and smooth muslces

Cell body = Cytoplasm with nucleus, cell organelles and Nissl’s granules

Parts of Neuron    Dendrites = Short fibres which branch rapidly and project

out of cell

Axon =    Single, long fibre, branched at distal endit (Refer fig. 21.1, page 317, NCERT - Biology, Class-XI)

Multipolar = : One axon and two or more dentrites

: Found in cerebral Cortex

Neuron    Bipolar =    : One axon and one dendrite

: Found in ratina of eye Unipolar =    : Cell body with axon only

: Found usually in the embryonic stage

Conduction of nerve impulse along axon

Polarised membrane/Resting Potential

In resting phase when neuron is not conducting an impulse, the axonal membrane is called polarised. This is due to difference in concentration of ions across the axonal membrane.

At Rest :

    Axoplasm inside the axon contain high conc. of K+ and low conc. of Na+.

    The fluid outside the axon contain low conc. of K+ and high conc. of Na+.

As a result the outer surface of axonal membrane is positively charged and inner surface is negatively charged. The electric potential difference across the resting plasma membrane is called resting potential.

Action Potential : When a nerve fibre is stimulated, the permeability of membrane to Na+ is greatly increased at the point of stimulus (rapid influx of Na+) and hence polarity of membrane is reversed and now membrane is said to be depolarised. The electric potential difference across the plasma membrane at that site is called action potential, which infact termed as nerve impulse.

Depolarisation is very rapid, so that conduction of nerve impulse along the entire length of axon occurs in fractions of second.

Transmission of Impulses at Synapse

1. At electrical synapses : Here the membrane of pre and post-syneptic neuron are in very close proximity. Electric current can flow directly from one neuron into other across these synapses, like impule conduction along a single axon.

2. At chemical synapses : Here the membrane of pre and post-syneptic neuron are separated by fluid filled space called synaptic cleft. Neurotransmitter are involved here.

When an impulse arrives at the axon terminal, it stimulates the movement of the synaptic vesicles towards membrane and they fuse with the plsama membrane and release their neurotransmitter in the syneptic cleft. These chemicals bind to specific receptors, present on the post-syneptic membrane. Their binding opens ion channels and allow the entry of ion which generate new potential in post synaptic neuron.

Human brain : Human brain is the major portion of central neural system.

Which is well protected by the skull.

The brain is surrounded by three cranial meninges—

1. Duramater—outer alyer

2. Arachnoid—middle layer

3. Piamter—Inner layer-remain incontact with brain

Parts of Brain

Fore brain	Mid brain	Hind brain
Cerebrum Thalamus Hypothalamus		Cerebellum Pons Medulla oblongata

Functions of pars of brain :

Cerebrum : Centre of intelligence, memory and imagination, reasoning,

judgement, expression of will power.

Thalamus : Acts as relay centre to receive and transmit general sensation of pain, touch and temperature.

Hypothalamus : Centre for regulation of body temperature, urge for eating and drinking.

Midbrain : Responsible to coordinate visual reflexes and auditory reflexes.

Cerebellum : Maintains posture and equilibrium of the body as well as coordinates and regulates voluntary movement.

Pons : Relays impulses between medulla oblongata and cerebral hemisphere and between the hemisphere of cerebrum and cerebellum. It also heps to regulate breathing.

Medulla oblongata : Centre that control heart beat, breathing, swallowing, salivation, sneezing, vomitting and coughing.

Reflex action : It is spontaneous, autonomic and mechanical response to

a stimulus that occurs at the level of spinal cord, without involvement of brain.

Reflex arc : The flow of nerve along the specific during reflex action. It

consist of—

1. A receptor

2. An Afferent neuron (sensory neuron)

3. An inter neuron

4. An efferent neuron (motor neuron)

5. An effector organ

Sensory neuron

Stimulus    Receptor

(REFLEX - ARC)        Inter neuron of spinal cord Response    Effector organ

motor neuron

Organ of Sight-Eye

Layer    Component    Function

1. External layer    Sclera    Protects and maintain shape of the

eye ball

Cornea    Outermost transparent portion of eye which allows light to enter

2. Middle layer    Choroid    Absorb light and prevent light from

being reflected within the eye ball.

Ciliary body    Holds lens, regulate shape of the

lens.

Iris    Control amount of light entering.

3. Inner layer    Retina    Vision in dim light, colour vision,

vision in bright light. Sends the image to brain through optical nerves.

(Refer-Fig. 21.6, Page 323 NCERT-Biology, Class XI)

Organ of Hearing–Ear

Portion of the ear   Component    Function

1. External ear    Pinna    Collect sound waves

External    Direct sound waves towards ear drum,

auditory canal    ear wax prevents the entry of foreign

bodies.

2. Middle ear    Tympanic    Acts as resonator that reproduces membrane    the vibration of sound.

Ear ossicles    Transmit sound waves to internal ear.

Eustachian tube    Helps in equalising the pressure

on either side of ear drum.

3. Internal ear    Cochlea    Hearing organ.

Vestebular    Balancing of body.

apparatus

(Refer Fig. 21.7, page 325-NCERT-Biology, Class XI)