Heat stress in U.S. may double by century's end

"Periods of extremely high heat are projected to double across the lower 48 states by 2100 if the world continues to emit high levels of greenhouse gases, according to a new study in Earth's Future, an American Geophysical Union journal.

The heat stress will be felt most strongly in areas with growing populations. The Pacific Northwest, central California and the Great Lakes region could experience as much as a threefold increase compared to the past 40 years. Heat stress occurs when both the temperature and relative humidity get high enough that the human body can't rid itself of the excess heat, leading to strokes, heat cramps and other health problems.

"Without doing any mitigation strategies, the impact of heat stress is likely to increase," said Ashok Mishra, a civil engineer at Clemson University and an author of the U.S. National Science Foundation-funded study.

Human-driven climate change is leading to an average increase in temperatures across the world. However, people don't necessarily notice a slow, even warming as much as an extreme event.

Mishra and co-authors wanted to see how heat stress would increase at the same time as a general increase in temperature and relative humidity. They assumed that while humans may experience higher temperatures on average in many areas, people will acclimatize to the new normal, but extremely high heat index peaks, above even the yearly median values, will continue to have negative impacts on human health.

While previous research has usually examined how extreme heat events may increase in severity, frequency and duration, most studies have looked at one of these in isolation. Mishra and his colleagues calculated how all these might increase together in the future under a high emissions scenario..."
Heat stress 

Managing Diabetes in the Heat

"How to keep your cool during the hottest time of year.

Did you know that people who have diabetes—both type 1 and type 2—feel the heat more than people who don’t have diabetes? Some reasons why:

• Certain diabetes complications, such as damage to blood vessels and nerves, can affect your sweat glands so your body can’t cool as effectively. That can lead to heat exhaustion and heat stroke, which is a medical emergency.
• People with diabetes get dehydrated (lose too much water from their bodies) more quickly. Not drinking enough liquids can raise blood sugar, and high blood sugar can make you urinate more, causing dehydration. Some commonly used medicines like diuretics (“water pills” to treat high blood pressure) can dehydrate you, too.
• High temperatures can change how your body uses insulin. You may need to test your blood sugar more often and adjust your insulin dose and what you eat and drink..."
  Diabetes and heat

Travel to Hot Climates

"Planning your next trip to a tropical climate like in the Caribbean? Pack your swimsuit and sunscreen, and follow these tips to prevent heat illness and injury when traveling in a hot climate.

It's winter time across the United States, and many travelers are looking to vacation in tropical areas to escape the cold temperatures at home. But traveling in hot climates can make you sick, especially if you are not accustomed to the heat. For most travelers who choose to relax on the beach or by the pool, heat illness and injury pose only a slight risk. However, people at highest risk are the elderly, young children, and people with chronic illnesses such as heart disease and diabetes. But even young and healthy people can get sick from heat if they participate in strenuous physical activities during hot weather. Dehydration, for example, makes people most susceptible to heat illness..."
Hot climates

Keep Your Cool in Hot Weather

"Now is the time to prepare for the high temperatures that kill hundreds of people every year. Extreme heat caused 7,415 heat-related deaths in the United States from 1999 to 2010 . Heat-related deaths and illness are preventable, yet annually many people succumb to extreme heat.

Take measures to stay cool, remain hydrated and to keep informed. Getting too hot can make you sick. You can become ill from the heat if your body can't compensate for it and properly cool you off. The main things affecting your body's ability to cool itself during extremely hot weather are:

• High humidity. When the humidity is high, sweat won't evaporate as quickly, which keeps your body from releasing heat as fast as it may need to.
• Personal factors. Age, obesity, fever, dehydration, heart disease, mental illness, poor circulation, sunburn, and prescription drug and alcohol use can play a role in whether a person can cool off enough in very hot weather..."
  Extreme heat

Diabetes in the Heat

"If you have diabetes, you know how important it is to have a care routine. Yet summer weather, with its high temperatures and extreme storms, can cause problems with that routine and make it more difficult to manage diabetes..."
Diabetes in the Heat

Extreme Heat: a Prevention Guide..

Tips from the  U.S. Centers for Disease Control and Prevention on dealing with extreme heat
See also: tips from the U.S. EPA

Don't Let the Heat Beat You

Tips for the Madison/Dane County Health Department:

"Every year at this time there are numerous news stories about the heat, offering solid advice on what to do when the weather gets very hot and humid. We hear these stories so often that many of us stop paying attention. But during the next week there will be five or six days when the temperature will be over 90 degrees so there are a few very important basics beyond the usual advice about staying cool and hydrated.

Here are three simple points to keep in mind.

1. Check in on elderly and disabled neighbors. Extreme heat can be very dangerous for them, and some might be shy or unable to ask for help. So please risk being a nosy neighbor. It will make this situation a lot less risky for them.

2. Don't push yourself or your kids too far with outdoor physical activities. Heatstroke can sneak up on you quickly, and it often requires a trip to the emergency room.

3. Do not leave your kids or your pets in a car, even with the motor and air conditioner running. A stalled engine will produce dangerously high temperatures very quickly, putting a child or pet at risk for brain damage and death. On hot or warm days, it's best to leave your pet at home, and to always take your child with you - no matter how short you think your errand will be..."