Mountain Meteorology

Glacier Travel

Mountain Hazards

Olympia Mountaineers

Basic Climbing Course

2015

Lecturer: Jeff Foster

Mountain Meteorology

Meteorology – the study of the atmosphere

and the processes that produce climate

and weather

Climate - the generally prevailing weather of

a region over a long period of time

Weather - the state of the atmosphere in

terms of temperature, humidity, wind, air

pressure, cloudiness, etc.

Mountain Meteorology

Washington’s Climate

Western Washington = humid maritime

cool, wet winters; warm, dry summers

Influenced by proximity of Pacific Ocean

(high heat storage of water)

Eastern Washington= semiarid continental

cold, dry winters; hot, dry summers

No oceanic influence

Mountain Meteorology

Washington

temperature

patterns

Washington’s Climate

Mountain Meterology

Washington precipitation patterns

Washington’s Climate

Mountain Meteorology

Washington precipitation patterns

Washington’s Climate

Mountain Meteorology

Location

Average annual

snowfall (inches)

Seattle 5

Paradise 671

Yakima 121

Washington’s Climate

Mountain Meteorology

Temperature lapse rate

Decrease in temperature with elevation in the lowest

layer of the atmosphere

Occurs faster in drier air, slower in moist air

Water has a high specific heat – the amount of heat

required to raise a unit mass by a specific temperature

Water vapor slow to give up or gain heat relative to air

So a moist air mass cools slower than a dry air mass as

it rises

Climate Processes

Mountain Meteorology

Temperature lapse rate

Westside annual mean = 1.4 (very moist air) to 1.9oF

(fairly dry air) per 1000 feet elevation

Eastside annual mean ≈ 1oF greater (air much drier)

If it's 50oF in Olympia, what's the temperature on top of

Mt. Rainier?

Climate Processes

Mountain Meteorology

Humidity

Absolute humidity – amount of water vapor in the air

Relative humidity – amount of water vapor in the air

as a percent of the maximum amount of water vapor

the air can hold

Climate Processes

Mountain Meteorology

Humidity

The warmer the air, the more water vapor it can hold

Climate Processes

Ab

so

lute

hu

mid

ity

Temperature

relative humidity

Mountain Meteorology

Humidity

If relative humidity rises to 100%, water vapor condenses out of air

to form water droplets

The result is cloud formation (even in moving air)

Climate Processes

extreme example: lenticular clouds

Mountain Meteorology

Humidity

If air temperature falls to the dewpoint (temperature at which

relative humidity =100%),

fog, dew, or frost forms

(requires calm air)

Climate Processes

fog forms in air near ground

dew and frost form on surfaces

> 32oF

< 32oF

Orographic precipitation & temperature

Mountain Meteorology

Climate and Topography

Mountain Meteorology

Rain shadow effect

Climate and Topography

Cascades Olympics

Mountain Meteorology

Unstable atmosphere

Atmospheric stability – resistance of the atmosphere to

to vertical motion

Stable Air

When an air parcel is colder and denser than the surrounding air,

it will stay at the same level or sink

Unstable Air

When an air parcel is warmer and less dense than the

surrounding air, it will rise

Weather Processes

Mountain Meteorology

Unstable atmosphere

Mechanisms of air lifting

Weather Processes

convective lifting

orographic lifting

frontal lifting

Mountain Meteorology

Thunderstorm formation - occurs when there is lifting

of air for long enough to a high-enough elevation

Weather Processes

Mountain Meteorology

Thunderstorm phenomena

Weather Processes

gust front

downdraft

Mountain Meteorology

Thunderstorm phenomena

Weather Processes

Hail

Lightning

cloud-to-cloud cloud-to-ground

Mountain Meteorology

Temperature inversions

Ele

vation

→

Temperature →

"undercast"

Weather and Topography

Hoh River Valley

Mountain Meteorology

Wind

Compression of air flowing over ridgetops or through

passes increases windspeed (partially due to Venturi

effect)

Weather Processes

ridge

Mountain Meteorology

Wind

Two clues to prevailing wind direction

Weather Processes

flag trees

rime ice

Mountain Meteorology

Wind

Weather Processes

snow banner

snow cornice

Mountain Meteorology

Local mountain winds

Weather Processes

Mountain Meteorology

Cold air ponding

Weather Processes

Mountain Meteorology

Movement of frontal systems is determined, in part,

by prevailing wind …

Frontal Systems

Mountain Meteorology

… and by the position

of the Jet Stream

Frontal Systems

Mountain Meteorology

Front = boundary between two dissimilar air masses

cold front warm front

Frontal Systems

Mountain Meteorology

Frontal Systems

Wind created as air flows

from high to low pressure

In Northern Hemisphere,

coriolis force causes counter-

clockwise diversion of wind

cooler air

warmer air

Isobar (lines of equal pressure) map

Mountain Meteorology

Frontal Systems

Seasonal patterns

Mountain Meteorology

What clouds can tell us

cirrus clouds

Clouds

Mountain Meteorology

What clouds can tell us

lenticular clouds

Clouds

Mountain Meteorology

What clouds can tell us

altostratus clouds

Clouds

Mountain Meteorology

What clouds can tell us

nimbostratus clouds

Clouds

Mountain Meteorology

What clouds can tell us

cumulus clouds

Clouds

Mountain Meteorology

What clouds can tell us

cumulonimbus clouds

Clouds

Mountain Meteorology

Washington Weather Records

Glacier Travel

Glacier Anatomy

valley glacier hanging glacier

Glacier Travel

Glacier Anatomy

Glacier Travel

Glacier Anatomy

Bergschrund

Glacier Travel

Glacier Anatomy

Moraines

terminal

lateral

firn line

Glacier Travel

Glacier Anatomy

below firn line

Crevasses

transverse

crevasses

Glacier Travel

Glacier Anatomy

Crevasses

radial

crevasses

Glacier Travel

Glacier Anatomy

Icefalls

Glacier Travel

Glacier Anatomy

seracs

Nisqually Glacier

Roping up

Minimum standard on Basic Glacier climbs is two ropes

of at least three climbers. Why?

Glacier Travel

Moving Across Glaciers

Roping up

end persons middle person

double bowlinerewoven figure 8prusiks

Glacier Travel

Moving Across Glaciers

Rope movement

rope between climbers almost taut

rope leader probes for crevasses

Glacier Travel

Moving Across Glaciers

Moving among crevasses

Best to travel at right angles to

crevasses, doing "end runs”

Don’t forget crevasses may

extend beyond their visible

ends as hidden crevasses

Glacier Travel

Moving Across Glaciers

Moving among crevasses

if traveling parallel to

crevasses, use

"echelon" formation

Whoever falls may pendulum!

Glacier Travel

Moving Across Glaciers

Crossing crevasses

narrow crevasse snow bridge over

large crevasse

use boot-axe belay

or

standing ice axe-

carabiner belay

Glacier Travel

Moving Across Glaciers

Crevasse rescue

If possible, practice with other students in advance

Review crevasse rescue figures in Freedom

Pay close attention during Z-pulley practice

Glacier Travel

Moving Across Glaciers

Climbing Hazards

Face It: Climbing Can Be Hazardous!

Climbing Hazards

Mountaineering Accidents

Climbing Hazards

Mountaineering Accidents

Climbing Hazards

Mountaineering Accidents

Climbing Hazards

Mountaineering Accidents

More Objective More Subjective

Less Control Over Occurrence

Climbing Hazards

Perception of Risk

AttitudeAssume there will always be

hazards

Cavalier vs. fearful

ExperiencePlanning

Encountering hazards on the climb

Learn from your and others'

mistakes

Climbing Hazards

Crevasses

Snow bridges

Hidden crevassesPresence may be indicated by small

holes or a depression in snow

In early season, may be no visual signs

Climbing Hazards

Crevasses

bergschrund

moat

Causes of rockfall

Freeze-thaw

Liquid water enters cracks in rocks

When it freezes, water expands, wedging rock apart

Eventually, chunk of rock detached from rest of rock

Melting of snow/ice holding rocks in place

On steep slopes that hold snow, small rocks are held in

place overnight by iced

When sun or warming temperature melts ice, rocks are

released

Climbers knocking down rocks (very common)

Mountain Hazards

Rockfall & Icefall

Watchout situations (rockfall)

Mountain Hazards

Rockfall & Icefall

rotten rock, freeze-thaw gully with climbers

Watchout situations

(icefall)

Climbing Hazards

Rockfall & Icefall

seracs

icefalls

What do you do if someone yells “Rock!”

a) Put on your helmet

b) Look up and try to find rock

c) Look down, flatten against cliff face

What does falling rock sound like?

a) No sound

b) Cracking sounds as rock bounces

c) Loud “whinging” sound as rock goes by

Mountain Hazards

Rockfall & Icefall

minimize

risk of

injury

prevention

avoidance

Mountain Hazards

Rockfall & Icefall

avoidanceMountain Hazards

High Winds

High wind in the open (e.g., at or above treeline)

hypothermia (lowering

of body temperature)

whiteout

(loss of visibility)

Mountain Hazards

High Winds

High wind in the forest

windthrow (uprooting)

windsnap

Mountain Hazards

Lightning

Potential injuriesCardiac arrest

Blunt head trauma

Perforated eardrum

Spinal cord damage

Superficial minor burns

Altered mental state

Mountain Hazards

Lightning

Prevention through avoidance is best option

Move away from direction of thunderstorm motion

Descend

What to do if caught in lightning

Avoid isolated trees and rocks

Stay away from water

Stay away from metal (move away from climbing gear)

Spread out (about 50 feet apart)

Insulate yourself from the ground

Crouch and cover head and ears

If you are out of shape, you put everyone in your party

at risk, at least of disappointment, if not life and limb

Engage in a pre-season conditioning regime

(this is why we require conditioners)

Start a climb well-hydrated and well-rested

(more on this later)

Let the climb/MOFA leaders know about health conditions

Mountain Hazards

Conditioning

Human heat loss/gain

radiation conduction convection

evaporation

Mountain Hazards

Heat & Cold Injuries

Human heat loss/gain

conduction + convection

Mountain Hazards

Heat & Cold Injuries

Hypothermia

Drop in core body temperature below 95oF

First degree

uncontrollable shivering

lethargy, apathy, confusion

lack of motor coordination

rapid heart rate

Second degree

shivering stops

delirium

slowing heart rate

Third degree

coma

ventricular fibrillation

Mountain Hazards

Heat & Cold Injuries

Hypothermia

Can happen at surprisingly warm temperatures

if you become wet and it’s windy

Treatment

get patient out of environment causing hypothermia

into warmer, dry, non-windy location

remove wet clothing

rewarm as rapidly as possible

offer warm liquids if patient conscious

may require healthy person sharing sleeping bag

with patient

Mountain Hazards

Heat & Cold Injuries

Frostbite

Freezing of exposed tissues

First degree ("frostnip")

superficial, quick recovery

Second degree

blistering but tissue recovers

permanent loss of sensitivity

Third degree

tissue death and loss

Mountain Hazards

Heat & Cold Injuries

Frostbite

Frostbite and hypothermia often go together!

Treatment

remove patient from source of frostbite

first degree

place injury next to warm body part

second/third degree

keep injury frozen

give plenty of fluids

evacuate to where thawing can be done

properly by medical professionals

Mountain Hazards

Heat & Cold Injuries

Heat Exhaustion

Cause: profuse sweating coupled w/ inadequate

hydration

Symptoms

nausea, dizziness, thirst, headache

Treatment

get patient into cool, shady location

administer fluids, slowly at first

replace electrolytes

Mountain Hazards

Heat & Cold Injuries

Sunburn

Snowblindness

Burning of cornea of eyes by UV-B

severe pain

swollen eyelids

headache

temporary blindness

symptoms take 6-12 hours to develop

Prevention

Wear dark glasses

transmit 5-10% of visible light

block 90-95% of UV-A and UV-B

sideshields if there is reflected light

Mountain Hazards

Heat & Cold Injuries

Physiological effects

Hard on kidneys

Increased risk of heat exhaustion and heat stroke

Increased risk of hypothermia and frostbite

Staying hydrated

Drink one water bottle (32 oz) every 4 hours

Water bottles vs. hydration packs

Mountain Hazards

Dehydration

Sources of contamination

Humans Animals

Types of contamination

Bacteria Viruses

Parasites

Giardia - very widespread now in backcountry;

cysts resist heat, cold, dessication

cysts trophozoites

Mountain Hazards

Contaminated Water

On top of Mt. Rainier, air pressure is

what percent of that at sea level?

Mountain Hazards

Effects of High Elevation

As elevation increases, the risk of the following

increases:

Sunburn – why?

Dehydration – why?

Hypothermia & frostbite – why?

Conditions caused by low oxygen pressure:

Cheynes-Stokes breathing

Acute Mountain Sickness (AMS)

High Altitude Pulmonary Edema (HAPE)

High Altitude Cerebral Edema (HACE)

Mountain Hazards

Effects of High Elevation

Acute Mountain Sickness

Cause: rapid ascent to higher elevation

50% of folks ascending to 8,000 to 14,000 ft

Symptoms

insomnia

listlessness

appetite loss

nausea & vomiting

lightheadedness or dizziness

Treatment

rest and hydration

if it gets worse, descend

Mountain Hazards

Effects of High Elevation

Pulmonary edema (HAPE)

Cause: body fluids leak into lungs

Symptoms

develop rapidly

breathlessness

labored breathing with bubbly noise

Cerebral edema (HACE)

Cause: blood vessels leak fluid into brain

Symptoms

headache

loss of coordination

confusion → hallucination

coma

Treatment of

HAPE & HACE

Descend!

Mountain Hazards

Effects of High Elevation