ONCE YOU GET THE STOVE GOING, THE TENT WARM & THE KCALS IN, YOUR BODY WILL START TO GENERATE WARMTH, AND THE NEXT MATTER WILL BE REDUCING IT LEAKING AWAY
THERE’S TWO PARTS TO STAYING WARM AT HIGH ALTITUDE
- GENERATING WARMTH
- KEEPING IT IN
BOTH ARE COMPROMISED BY THE ENVIRONMENT THAT RETARDS METABOLIC FUNCTION & IS INHERANTLY COLD. EVERYTHING FROM THE WAY A STOVE WORKS, THE WAY YOU EAT, HOW TENTS & SLEEPING BAGS WORK AND HOW YOUR GEAR WORKS HAS A ROLE IN STAYING WARM, THE MORE HOLES YOU PLUG THE WARMER YOU WILL STAY. THINK OF IT AS WATER THAT NEEDS TO BE HEATED THEN STOPPED FROM LEAKING AWAY.
GENERATING WARMTH
THERE’S 2 PLACES HEAT COMES FROM IN A COLD ENVIRONMENT;
- YOUR STOVE
- YOUR METABOLISM
BOTH ARE PRECIOUS, FINELY TUNED MECHANISMS THAT USED RIGHT WILL KEEP YOU FUNCTIONAL TO DEPTHS OF COLD AT A SCIENCE FICTIONAL LEVEL.
YOUR STOVE WORKS BY TURNING LIQUID FUEL INTO GAS AND IGNITING IT AND THAT WORKS ON A TEMPERATURE DIFFERENTIAL BETWEEN THE LIQUID IN THE CANISTER AND ATMOSPHERE – THE GREATER THE DIFFERENCE THE BETTER IT BURNS – AND THE MORE YOU CAN DO TO PUSH THAT DIFFERENCE THE BETTER.
THE #1 THING YOU CAN DO TO MAKE A STOVE BURN BETTER WHEN HIGH & COLD IS INCREASE THE AMBIENT TEMPERATURE OF THE TENT. THIS TILTS THE TEMPERATURE DIFFERENTIAL TO THE ENVIRONMENT END OF THE PROCESS. THE ISSUE HERE IS YOU NEED TO GET THE STOVE GOING TO DO THIS, BUT EVEN QUITE A SMALL INCREASE IN AMBIENT TEMPERATURE HAS SURPRISING RESULTS – LITTLE ENOUGH THAT A TRICK OR TWO OF WARMING OF THE CANISTER LONG ENOUGH WILL DO IT.
WHEN LIT, RUN THE STOVE WITHOUT A POT ON IT FOR A MINUTE OR TWO & EITHER REMOVE THE STOVES WIND SHIELD OR LIFT THE POT REGULARLY WHEN COOKING TO KEEP THE AMBIENT TEMPERATURE UP. (NEEDLESS TO SAY ALL THIS GOES WITH THE SOP’S OF USING A STOVE INSIDE A TENT, USING A HANGING STOVE & CO ISSUES).
THIS PROCESS DESERVES EXTRA GAS BEING CARRIED AS IT INCREASES LIVABILITY (A LOT OF FORAYS GET LIMITED BECAUSE THE GAS IS GETTING LOW) AND IS GREATLY ENHANCED INSIDE A DOUBLE-SKIN TENT – TO THE POINT THAT OVER A LONG ENOUGH TRIP IT ADDS UP WELL.
SOME STOVES ARE BETTER SUITED TO THE TASK, WITH REMOTE CANNISTER STOVES THAT HAVE ATOMIZER TUBES (LIKE THE FIRE MAPLE BLADE II WE ADVOCATE) BEING EASILY THE BEST.
IF YOU’RE NOT IN A TENT (WHICH ASKS THE QUESTION OF WHY?) YOU’RE GOING TO HAVE TO GO WITH ADDRESSING THE CANISTER END OF THE PROCESS, WARMING IT ENOUGH SO THE LIQUID IS EFFICIENTLY COMBUSTIBLE GAS (THIS IS WHERE THE ATOMIZER TUBE & REMOTE CANNISTER REALLY MATTERS). SWAPPING OUT CANNISTERS KEPT WARM IN YOUR JACKET WILL GET A STOVE STARTED, BUT TO KEEP GOING WITHOUT A SIGNIFICANT LEVEL OF MESSING ABOUT YOU NEED TO KEEP IT WARM. A THERMAL COVER WILL HELP A BIT, BUT THE BEST METHOD IS CAPTURING HEAT OFF THE RUNNING STOVE EITHER BY STACKING THE STOVE INSIDE A LARGE POT OR BY HAVING THE STOVE CLOSE ENOUGH TO THE FLAME TO GET SOME OF THE WARMTH (NOTE; THOUGH AN OBVIOUS & CATASTROPHIC RISK, IT’S ACTUALLY HARDER TO BLOW A CANNISTER UP THAN YOU MIGHT IMAGINE AND WORTH THE EXPERIMENT TO SEE).
USED IN A TENT THE STOVE PROVIDES BOTH AMBIENT WARMTH & METABOLIC WARMTH BY COOKING YOUR FOOD, AND IS A FAR CRY BETTER THAN IN THE OPEN WHERE YOU GET ONLY THE LATTER. IT IS EASILY WORTH IT TO CARRY AN ULTRALIGHT TENT RATHER THAN 2 BIVY BAGS FOR THIS ON ASCENTS AT ALTITUDES THAT COMPROMISE YOUR METABOLISM FROM KCAL & OXYGEN UPTAKE.
THE FOOD YOU EAT & LIQUIDS YOU CONSUME HAVE A HUGE IMPACT ON STAYING WARM, AND ABOVE 7000m METABOLIZING FAT DROPS OFF WHICH IS THE USUAL FUEL SOURCE FOR STAYING WARM. THIS MEANS CARBOHYDRATES AS SIMPLE AS YOU CAN TAKE THEM WITHOUT THEM BEING STRAIGHT SUGAR. FORGET PROTEIN & IDEAS ABOUT COCONUT OIL, TO KEEP THE FIRES BURNING THE ONLY EFFICIENT FUEL UP THAT HIGH IS STUFF LIKE INSTANT NOODLES, CHRISTMAS CAKE & DEHY RICE, WITH AS MUCH LIQUID CONTENT TO STILL BE PALATABLE. WASHING IT ALL DOWN WITH SWEETENED TEA OR POWDERED STUFF HELPS (THOUGH HIGH TECH POWDERS SEEM TO LOSE THEIR YUM THE HIGHER YOU GO), AND UNSWEETENED CONDENSED MILK SEEMS TO STAY STOMACHABLE LONGER THAN THE SWEETENED STUFF.
ONCE YOU GET THE STOVE GOING, THE TENT WARM & THE KCALS IN, YOUR BODY WILL START TO GENERATE WARMTH, AND THE NEXT MATTER WILL BE REDUCING IT LEAKING AWAY
KEEPING WARMTH IN
IT DOESN’T TAKE LONG TO REALIZE WARMTH IS WORTH MORE THAN ANYTHING WHEN YOU’RE ON A COLD MOUNTAIN, AND LETTING IT WHISP AWAY INTO THE ETHER WITH BAD PRACTICES SOON BECOMES A CRIME. FIGHTS HAVE BROKEN OUT. ALL THAT WARMTH TAKES A LOT TO EARN IN WEIGHT CARRIED, METHODS APPLIED & STRATEGY – DON’T LOSE IT ANY FASTER THAN YOU NEED TO.
IT’S IMPORTANT TO UNDERSTAND THAT ONCE YOU’VE GOT KCALS INSIDE YOU AND STEP INTO A COLD ENVIRONMENT THERE’S NOWHERE ELSE FOR HEAT TO COME FROM EXCEPT INTERNALLY. CLOTHING, SLEEPING BAGS, BOOTS ETC DON’T PRODUCE ANY WARMTH, THEY ONLY INSULATE AGAINST IT’S LOSS AND ALL YOU CAN DO IS SLOW THAT. EVEN THE EFFECTS OF RADIANT HEAT FROM THE SUN ONLY SLOW THE DRAIN WHEN YOU ARE SOMEWHERE AS COLD AS THE FLANKS OF GENYEN OR K2 – THE ENTIRE JOB IS UP TO YOUR GEARS ABILITY TO INSULATE.
THERE’S 2 PARTS TO RETAINING WARMTH
- WHEN MOVING
- WHEN STATIC
DIFFERENT ASCENTS HAVE DIFFERENT MIXES OF THIS, AND WHERE EVEREST IS A SLOW PLUG UPWARDS WITH A LOT OF TIME WAITING, K2’S NORTH RIDGE OR A 6500m PEAK IN A TIBETAN WINTER HAS A LOT MORE MOVEMENT INVOLVED.
ON THE MOVE, WHEN YOU ARE OUT & EXPOSED TO THE WIND, YOU ARE BALANCING METABOLIC OUTPUT WITH THE AIR’S ABILITY TO STRIP IT AWAY. THIS IS BASIC STUFF, AND CLOTHING THAT VENTS ENOUGH TO MINIMIZING SWEATING (BY BEING EASY ENOUGH TO USE TO PREVENT HEAT ACCUMULATION BEFORE IT BECOMES AND ISSUE) THEN CAN BE ZIPPED UP TO INSULATE WHEN YOU SLOW OR STOP ADDRESSES IT. ANY CLOTHING GENUINELY AIMED AT HIGH ALTITUDE USE WILL HAVE A WAY OF ADDRESSING THIS, TO VARYING DEGREES OF SUCCESS (OF BOTH THE GEAR AND THE USER).
BECAUSE HEAT IS LOST IN SEVERAL WAYS, REDUCING THE EFFECTS OF WIND – BECAUSE IT INVOLVES THE LARGEST PROFILE OF YOUR SURFACE AREA – GOES THE FURTHEST. THIS MEANS WIND-BLOCKING FABRICS & CLOTHES THAT ARE WELL FITTED THUS REDUCING SURFACE AREA. FLAPPING MATERIAL LITERALLY DRAWS HEAT INTO IT BECAUSE IT SHARES SPACE WITH THE AREA UNDER YOUR WINDPROOFING, WHICH IS THEN SUPERCOOLED FROM THE OUTSIDE OF THE GARMENT, IN THE SAME WAY A TENT WITHOUT ENOUGH SPACE BETWEEN INNER AND THE FLY ALLOWS COLD ESCAPE THROUGH AS THE SIDES TOUCH WHEN THE WIND HITS.
NOT MOVING PRESENTS EVEN BIGGER INSULATION ISSUES BECAUSE YOUR METABOLISM SLOWS, AND STANDING AROUND WAITING FOR THE FIXED LINES TO FREE UP CAN BE THE COLDEST TIMES ON A TRIP. ON K2’S NORTH SIDE & IN TIBET THIS IS KEPT TO A MINIMUM AND BASICALLY ONLY ON BELAYS, AND CAN BE MITIGATED TO SOME EXTENT WITH EATING & PLANNING. AS SOON AS YOU STOP ACTIVITY IT IS VITAL YOU ZIP UP & GET YOUR COLD GEAR ON WHILST YOUR ARE PUTTING OUT HEAT TO CAPTURE – WAITING TO COOL IS SIMPLY LETTING KCALS BLEED AWAY, AND ONCE COOL IT’S VERY HARD TO WARM BACK UP AGAIN WHEN NOT MOVING.
A HUGE PART OF BEING UP HIGH IS THE STASIS OF BEING IN A TENT, AND CREATING & MAINTAINING A STABLE WARM CELL OF HABITABILITY ON A FROZEN MOUNTAIN IS A SERIES OF SKILLS THAT’S FOUNDATIONAL TO EXPEDITION CLIMBING. AS WE ALWAYS TELL CLIMBERS – “YOUR ABILITY TO CLIMB HIGH MOUNTAINS IS YOUR ABILITY TO STAY ON THEM”.
GETTING THE STOVE GOING TO EAT IS ONLY PART OF THE EQUATION AND ONLY AS EFFECTIVE AS YOU CAPACITY TO CONTAIN THE WARMTH YOU MAKE, AND ROUTINELY WE SEE CLIMBERS UNAWARE HOW MUCH HEAT THEY COULD BE RETAINING BUT ARE NOT. WE ADDRESS THIS BY HAVING A TICK LIST OF WAYS HEAT IS LOST AND COVERING AS MUCH AS WE CAN IN AN ALPINE CONTEXT
- ADVECTION – MOVING A COLD MASS IN OR A HOT MASS OUT
- CONDUCTION – LOSING HEAT INTO THE GROUND & MOISTURE
- CONVECTION – HEAT BEING SUCKED AWAY
- RADIATION – HEAT RADIATING OUT INTO THE AIR
YES THERES THE FINER PHYSICS OF ALL THIS, WITH OVERLAP OF ALL OF THEM, BUT FUNCTIONALLY THESE FORMS OF HEAT LOSS IN A TENT ON A COLD PEAK ARE DEALT WITH THESE WAYS
ADVECTION
- KEEP THE SNOW BAG IN THE VESTIBULE, NOT IN THE MAIN TENT
- KEEP METAL OUTSIDE
- INSULATE WATER BOTTLES
CONDUCTION
- COVER THE FLOOR WITH MATS & PACKS
- STICK YOUR BOOT SHELL BETWEEN YOU & THE SIDE OF THE TENT
- KEEP THE STOVE OFF THE FLOOR
- HAVE A CLOSED CELL MAT IN YOUR SLEEPING SYSTEM
- KEEP SNOW AWAY FROM THE SIDES OF THE TENTS
- VENT STEAM FROM THE TENTS HIGHEST POINT
- BLAST THE STOVE TO KEEP THE TENT FREE OF FROST
CONVECTION
- PITCH THE TENT TO NOT FLAP
- USE DOUBLE SKIN TENTS WHERE YOU CAN
- SEAL OFF THE FLY WITH SNOW FLAPS OR WIND BREAKS
- VENT THE INNER INTO THE VESTIBULE, NOT THE VESTIBULE INTO THE OUTSIDE
RADIATION
- VENT YOUR BODY HEAT INTO YOUR TENT SPACE & SLEEPING BAG
- HEAT SOME WATER TO BOILING
- KEEP POTS OF HOT WATER OFF THE FLOOR SO HEAT RADIATES OUT EVENLY
- ALLOW HEAT FROM THE STOVE TO BLEED INTO THE AIR
- DON’T INVEST TOO MUCH INTO THE IDEA REFLECTING HEAT – IT’S NOT VERY EFFICIENT
PUT TOGETHER ALL THIS MAKES A VERY HABITABLE SPACE, WHICH MANAGED WELL IS SUSTAINABLE WITH A FEW BASICS
- DON’T OPEN THE INNER & OUTER DOORS AT THE SAME TIME
- DRY THE TENT WITH A FEW BLASTS OF THE STOVE BEFORE LETTING IT COOL
- PREP & PACK AS MUCH AS YOU CAN BEFORE EXITING THE TENT
- USE A PISS BOTTLE
- COOK, MELT & EAT OVER SEVERAL ROUNDS TO KEEP HEAT ENTERING THE SYSTEM
GETTING ALL THIS RIGHT IS HOW EXPEDITION ALPINISTS STAY IN THE HIGH MOUNTAIN ENVIRONMENT LONG ENOUGH TO GET THINGS DONE.
