Heat and humidity conspire for discomfort, danger

July 21, 2011 in Health

(AP) -- When it comes to the discomfort and health risks of the current heat wave, it's not just the heat or the humidity - it's both.

The temperature conspires with the amount of moisture in the air to make it hard for the human body to cool itself.

When people get hot, the body tries to cool down by moving extra blood to the skin and by sweating.

Blood in the tiny vessels near the skin can dissipate heat into the air, if the air is cooler than the body. But that doesn't work if the air is as hot as the body or hotter.

Sweat helps, because when water evaporates it removes heat. But the more moisture already in the air - the higher the humidity - the less evaporation can occur.

Those two processes account for more than 90 percent of the body's ability to dissipate heat, and when they aren't working, trouble can come from , and even death.

©2011 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

not rated yet  

Rank not rated yet
Related Stories
Relevant PhysicsForums posts

More news stories

P&G to add latches to make detergent packs safer

(AP) -- Procter & Gamble says it will change the design of packaging for its miniature laundry detergent product to deter children from eating the brightly colored packets that look like candy.

Health created 9 minutes ago | popularity not rated yet | comments 0

In Spain, 70 percent of women use contraceptives during their first sexual encounter

Contraceptive use in Spain during the first sexual encounter is similar to other European countries. However, there are some geographical differences between Spanish regions: women in Murcia use contraceptives ...

Health created 1 hour ago | popularity not rated yet | comments 0

WHO target to cut early chronic illness deaths

The World Health Organization announced on Friday it was set to approve a new target to reduce premature deaths from chronic illnesses such as heart disease by a quarter by 2025.

Health created 1 hour ago | popularity not rated yet | comments 0

Better response plans needed for children exposed to domestic violence

(Medical Xpress) -- Each year, millions of children are exposed to domestic violence, a traumatic experience that has been associated with cognitive, behavioral, social and emotional problems in childhood ...

Health created 3 hours ago | popularity not rated yet | comments 0

Australia defiant on WTO cigarette challenge

Australia said Friday it would "vigorously defend" itself against complaints about its plan for plain cigarette packaging made by Honduras and Ukraine to the World Trade Organisation.

Health created 4 hours ago | popularity 5 / 5 (1) | comments 0


Cancer may require simpler genetic mutations than previously thought

Chromosomal deletions in DNA often involve just one of two gene copies inherited from either parent. But scientists haven't known how a deletion in one gene from one parent, called a "hemizygous" deletion, can contribute ...

World Health Assembly endorses new plan to increase global access to vaccines

Ministers of Health from 194 countries at the Sixty-fifth World Health Assembly today endorsed a landmark Global Vaccine Action Plan (GVAP), a roadmap to prevent millions of deaths by 2020 through more equitable access to ...

Inherited DNA change explains overactive leukemia gene

A small inherited change in DNA is largely responsible for overactivating a gene linked to poor treatment response in people with acute leukemia.

Of mice and mental models: Neuroscientific implications of risk-optimized behavior in the mouse

(Medical Xpress) -- Regardless of an organism’s biological complexity, every encephalized animal continuously makes under-informed behavioral choices that can have serious consequences. Despite its ubiquity, ...

Implantable pain disk may help those with cancer

An estimated 3.5 million cancer patients around the globe are in severe pain from their disease, but many get no relief.

First study to suggest that the immune system may protect against Alzheimer's changes in humans

Recent work in mice suggested that the immune system is involved in removing beta-amyloid, the main Alzheimer's-causing substance in the brain. Researchers have now shown for the first time that this may apply in humans.