The outdoor temperature can have a big impact on our daily lives. As the mercury falls, it triggers a cascade of changes both outdoors and indoors. Understanding what happens when temperatures drop can help you plan and prepare appropriately.
How Cold Temperatures Affect the Human Body
Our bodies are finely tuned to maintain a near-constant internal temperature of 98.6°F (37°C). However, we have to work harder to maintain this temperature when the outdoors turns chilly. Here’s what happens:
Constriction of Blood Vessels
In cold weather, blood vessels near the skin constrict to reduce blood flow to the skin and extremities. This helps limit heat loss from the circulatory system. However, it can leave hands and feet feeling cold.
Increased Metabolic Rate
To generate body heat, your metabolic rate has to increase. Shivering is one way the body does this. Eating extra calories also helps fuel your metabolic furnace against the cold.
Change in Blood Composition
Cold causes your body to exhibit a few changes in your blood:
- Increased red blood cell count – This improves oxygen delivery to tissues, including muscles working hard to shiver.
- Increased blood glucose levels – Your body mobilizes glucose reserves to provide ready energy to generate heat.
- Increased cholesterol levels – Cholesterol uptake by cells may improve to reinforce cell membranes against freezing temperatures.
Lowered Immune Response
Research shows that immune system functions may be somewhat suppressed in cold weather. This may partially explain why rates of coughs, colds, and flu tend to be higher when the mercury drops.
Increased Urine Production
You may find yourself urinating more frequently when it’s cold outside. This is due to reduced ADH (antidiuretic hormone). Your kidneys allow more water to leave the body so that the blood thickens slightly, lowering the freezing point.
Muscle Tension
The body’s efforts to conserve heat can lead to increased muscle tension and discomfort. This may aggravate conditions like fibromyalgia during cold snaps. Gentle stretching and massage may provide relief.
Joint Pain
Lots of people report increased arthritis pain and joint stiffness when temperatures fall. This results from the body shunting blood away from extremities to the core. Staying active with gentle range-of-motion exercises can help.
Raynaud’s Syndrome
In some people, cold triggers Raynaud’s syndrome. This causes severe narrowing of blood vessels in the fingers and toes. It can lead to blanching of the skin, numbness, and pain. Frequent episodes may result in sores or ulcers on the affected areas.
Hypothermia
Without adequate clothing protection, being in cold conditions for too long leads to a dangerously low core body temperature (hypothermia). Warning signs include intense shivering, confusion, sleepiness, slowed breathing, and loss of consciousness. Seek medical help immediately if hypothermia is suspected.
How Plants and Animals Cope with the Cold
Plants and animals have evolved some remarkable strategies for surviving frigid conditions:
Migration
Many bird species escape the cold by migrating to warmer regions for the winter. Examples include robins, swallows, hummingbirds, ducks, and geese. Some insects also migrate seasonally.
Hibernation
Certain mammals like bears, hedgehogs, and ground squirrels enter a dormant state called hibernation in winter. Their heart rate, breathing rate, body temperature and metabolism slow down drastically, allowing them to conserve energy through the coldest months.
Insulation
Warm-blooded animals rely on fur, feathers and fat layers to insulate themselves from the cold. Polar bears have transparent fur that traps heat from the sun. Beavers have a dense underfur overlaid with longer guard hairs for waterproofing. Birds fluff up their feathers to trap more air.
Countercurrent Heat Exchange
Animals like penguins and whales have a countercurrent heat exchange system in their fins or flukes. Arteries carrying warm blood are right next to veins carrying cool blood from the extremities. This allows for efficient recycling of body heat.
Antifreeze Proteins
Some cold-weather fish and insects produce antifreeze proteins that lower the freezing point of their blood and bodily fluids. This prevents ice crystals from forming and damaging cells and tissues.
Deciduous Habit
Deciduous plants from temperate regions shed their leaves in fall to conserve resources before winter dormancy. Shedding leaves also reduces transpiration during cold periods when the ground may be frozen.
Cold Acclimation
Perennial plants like evergreens undergo physiological changes during fall to increase freezing tolerance. This involves changes in gene expression, cell membranes, and production of antifreeze compounds.
Coping Mechanisms
Animals have some helpful behavioral adaptations for cold weather, too. Huddling together offers social animals more warmth. Turning away from the wind helps reduce convective heat loss. Seeking out sheltered spots can diminish chilling effects. Having furry feet like arctic foxes improves traction on snow and ice.
How Colder Temperatures Impact Inanimate Objects
The influence of cold isn’t just limited to living organisms. Frigid conditions also have significant physical effects on non-living items:
Battery Capacity
Batteries have reduced capacity in low temperatures. The chemical reactions that produce electrical current slow down. Performance can drop 20% or more below freezing.
Automobile Starting
Cranking an engine is more difficult in cold weather since the engine oil thickens, providing more resistance. Gasoline may also vaporize more sluggishly from reduced cylinder pressure.
Snow and Ice Accumulation
Freezing temperatures allow snow to accumulate from winter precipitation events. Melting snow often refreezes as ice, which can make roads and walkways slick. Black ice blends right into the pavement.
Contraction of Materials
Most materials contract when cooled due to the slowdown of molecular motion. This shrinking can lead to gaps at joints and weaker structural integrity. Roads and pipes may crack under contracting stress.
Metal Brittleness
Many metals and alloys, especially those already heat-treated, become less ductile at low temperatures. Trying to bend or shape cold metal tends to cause fracturing instead of deforming it.
Reduced Elasticity
The elasticity of rubber and many plastics diminishes significantly in cold conditions. Tires lose flexibility and shock absorption. O-rings and gaskets may fail from reduced compliance.
Lower Air Density
Colder air compresses and gets denser relative to warm air. At the same temperature and pressure, cold air has about 10% higher density. This impacts aerodynamics for things like airplanes.
Increased Air Viscosity
When air temperature drops substantially below freezing, the viscosity or “thickness” of the air increases modestly. This adds extra fluid drag on objects moving through it, like cars.
Impeded Chemical Reactions
Many chemical reactions, like the curing of concrete, proceed more slowly at cold temperatures. Some necessary reactions can even be temporarily halted under freezing conditions. Processes may require heating or insulation for proper activity.
Reduced Solubility
Solids are generally less soluble in cold solvents than warm ones. This applies to gases dissolved in liquids as well. Colder water holds less oxygen, which can impact aquatic life. Cold beer doesn’t retain as much fizz.
Destructive Freeze-Thaw Cycles
In areas where temperatures fluctuate frequently around the freezing point, the repeated freeze-thaw cycle produces physical stresses that can damage materials like concrete, rock and pipework through fracturing and erosion.
How Colder Weather Changes Society and Infrastructure
Beyond influencing organisms and materials, chilly weather causes an array of economic, social and infrastructure impacts:
Increased Energy Demand
As heating needs rise, energy usage spikes higher, sometimes testing the limits of supply grids. Shortages can lead to brownouts or blackouts. High demand may cause fuel prices to increase.
Boosted Seasonal Employment
Retailers add extra staff to handle higher sales of cold weather apparel, equipment and supplies. Additional snow removal crews may also be hired to keep roads, sidewalks and parking lots cleared.
Higher Operating Costs
Schools, businesses and municipalities face greater costs for heating, snow clearance, cold-weather gear and insurance claims related to the conditions.
Logistical Challenges
Icy roads reduce traffic flow, road freight, and public transit reliability. Airlines have to ground more flights due to weather. Slowdowns in shipping can create inventory issues.
Infrastructure Damage
Freezing temperatures place added strain on roads, bridges, dams, and power/water lines. Pipes may burst. Road salt and freeze-thaw erosion can corrode infrastructure. Tree branches may snap under heavy snow loads.
Public Safety Risks
Icy travel surfaces lead to increased traffic accidents. Frigid temperatures can also result in more falls and injuries. Overexertion with snow shoveling triggers heart attacks. Fires pose greater hazards when hydrants freeze.
Changes in Recreation
Colder weather allows for more winter-based activities like skiing, snowboarding, skating, and pond hockey. But it can curtail or close down regular parks and playgrounds, especially if these areas aren’t adequately plowed or maintained.
Impacts to Agriculture
Cold snaps threaten livestock and crop yields. Ranchers have to protect and feed cattle. Farmers use row covers, heaters and wind machines to prevent frost damage in orchards and vineyards.
Shortened Construction Season
Outdoor construction work may halt for the winter if temperatures prevent the proper curing of materials like concrete. Projects already underway require weather protection and heating.
Benefits to Environment
Colder conditions offer some ecological benefits. Lower temperatures reduce harmful algal blooms in lakes and reservoirs. Natural compaction of snow adds moisture to the soil. Some invasive pests and parasites may be mitigated by winter’s harsh conditions.
How to Prepare Your Home for Colder Weather
Colder outdoor air infiltrating a building can create discomfort. But you can take steps to fortify your home against plunging temperatures:
- Perform a pre-winter inspection of walls, windows, doors, flashing and roofing to identify and seal any air leaks or gaps. Cover crawl space vents and insulate attic hatches.
- Have your heating system professionally serviced to ensure it’s in good working order before you need it. Replace air filters and clear intake/exhaust vents of debris, snow or ice. Consider a programmable thermostat.
- Insulate any areas that feel drafty. Boost attic insulation to recommended R-value for your region. Add weather stripping around leaky doors and windows. Caulk or foam seal gaps along sills, trim, piping and wiring penetrations.
- Protect water lines from freezing. Insulate pipes in crawl spaces, attics and basements. Wrap outdoor spigots. Disconnect garden hoses. Shut off and drain any isolated or unheated lines.
- Have fireplaces and wood stoves cleaned to improve efficiency and reduce risk of fires, carbon monoxide issues or smoke spillage. Stock up on firewood. Inspect flues.
- Reverse ceiling fan direction to run clockwise, pulling air up and recirculating warm air that collects near the ceiling.
- Open blinds and curtains when sunny to gain passive solar heat through windows. Close them at night for insulation. Install thermal curtains for added warmth.
- Consider installing storm windows over single pane windows or replacing inefficient windows entirely. Use plastic window insulation film to reduce drafts.
- Move any outdoor furniture, grills, potted plants, hoses, etc into garages or sheds to prevent damage. Turn off, drain and winterize any exterior plumbing fixtures.
- Examine gutters and downspouts. Clear leaves or debris. Make sure water can drain away from the house to avoid ice damming on the roof.
How to Prepare Your Vehicle for Colder Temperatures
Vehicles also require some additional care before and during cold snaps:
- Check coolant level and antifreeze concentration. Make sure it provides adequate freeze protection and cooling. Flush radiator if dirty. Replace coolant every 3-5 years.
- Inspect battery age and terminals. Cold saps battery strength. Clean any corrosion on terminals and tighten connections.
- Consider upgrading to a higher cold cranking amp (CCA) battery if yours is over 3 years old. The newer the better for cold starts.
- Check condition of belts and hoses. Ensure clamps are tight. Replace any cracked or brittle hoses.
- Make sure heater and defroster work properly. Lubricate door, window and sunroof seals with silicon spray to prevent freezing shut.
- Get oil changed if needed – check that it has proper viscosity rating for cold operation (0W or 5W). Thinner oils improve startability.
- Examine wipers and washer fluid. Refill fluid with winter formula. Replace worn wiper blades. Warm washer nozzles can help thaw.
- Inspect tire tread depth and pressure. Consider snow tires for improved traction and control. All-weather tires are a compromise option.
- Prepare an emergency cold weather kit – scraper, brush, flashlight, warm clothes, blankets, snacks, medication, jumper cables, flares, traction mats, shovel, etc.
- Winterize any RVs or equipment trailers. Add RV antifreeze, drain tanks, cover windows, disconnect batteries, shut off propane.
How to Dress for Cold Weather
Bundling up appropriately helps your body retain precious heat when it’s frigid outside:
Focus on Layers
Layering clothing traps air and lets you adjust your level of insulation. Avoid sweating – shed layers as needed.
- Base layer – Synthetic or merino wool to wick moisture.
- Mid layer – Sweater or fleece for insulation.
- Outer layer – Wind/water-resistant coat or shell.
Cover Extremities
Don’t forget a warm hat, gloves, thick socks and insulated boots. Mittens are warmer than gloves.
Balaclavas or Neck Warmers
Covering your head, neck and face protects from freezing skin or wind burn.
Choose Moisture-Wicking Fabrics
Avoid cotton, which holds moisture. Opt for performance synthetics that wick sweat away.
Wind Protection
Breaking the wind, even with a light shell, makes a huge warmth difference.
Layer Pockets
Strategic use of pockets to hold chemical or electric hand warmers can add heat.
How to Exercise Safely in Cold Weather
Don’t let chillier weather derail your fitness routine. Just take a few reasonable precautions:
- Dress in insulating, moisture-wicking layers with a windproof outer layer. Shed layers as you heat up.
- Cover your extremities well – gloves, hat, socks. Flesh exposed to frigid air will cool you down fast.
- Use petroleum jelly or anti-chafing balms to protect exposed skin.
- Wear bright, reflective outerwear if exercising near roads in the dark.
- Stay hydrated and fuel up on calories to power you through cold workouts.
- Start activity slowly and gauge effort by perceived exertion rather than heart rate, which will be lower in the cold.
- Pick flat, clear routes to avoid slips on snow or ice. Avoid overdoing high-impact activities to prevent strains or sprains.
- Bring a charged phone in case of emergency. Stick to familiar, well-traveled areas and advise someone of your route.
- Know signs of hypothermia and frostbite. Adjust activity or get indoors if concerned.
- Listen to your body. Dial back intensity if uncomfortable or experiencing unusual pains.
Exercising in the chill carries risks if not smart about it, but offers fantastic scenery and solitude rewards. Don’t hibernate all winter – just be prepared.
Safety Tips to Follow When Temperatures Plummet
Frigid weather poses some unique hazards. Keep these safety guidelines in mind:
- Layer up when heading outdoors and limit exposed skin. Take extra sets of dry gloves and socks.
- Stay hydrated and fuel up with high-calorie foods and warm drinks. Avoid caffeine and alcohol.
- Apply sunscreen to prevent windburn even on cloudy days. Use lip balm and moisturizers.
- Wear proper winter boots with insulation and good traction. Take short, flat-footed steps on ice.
- Check on elderly or vulnerable neighbors to ensure their home heating is adequate.
- Never run engines, heaters, grills or generators indoors or in garages where carbon monoxide can collect.
- Ensure all gas appliances are properly ventilated and chimneys are clear of ice or snow buildup.
- Avoid overexertion while shoveling snow. Take breaks and push rather than lift when possible.
- Allow extra stopping distance while driving. Don’t stomp on brakes – pump them to avoid slides.
- Check and refresh emergency supplies like food, water, batteries, phone chargers, and medications.
- Prevent pipes from freezing by keeping faucets dripping and opening cabinets beneath sinks.
Staying vigilant against winter hazards will help you weather the cold safely. Use good judgment when venturing out into freezing temperatures.
How Society Adapts to Frigid Temperatures
Humans demonstrate remarkable resilience in adapting to the challenges of extreme cold:
Architecture
Homes in cold climates often have small windows, thick insulated walls, steep roofs, and minimal projections. Interiors maximize south solar exposure.
Heating Technology
Innovations like central heating, thermal glass, geothermal systems, and high-efficiency furnaces make indoor living more comfortable. Double-pane windows and programmable thermostats help conserve energy.
Insulating Materials
Synthetic fabrics like polyester and fleece along with down, wool, and newer high-tech materials create lightweight but ultra-warm clothing and bedding options. Foam insulation, sealants and weather stripping conserve building heat.