Monthly Archives: August 2017

Harvey Flooding

Catastrophic rains continue to plague Texas as the remnants of Hurricane Harvey deluge the area.

This image shows the rainfall in just the past 24 hours. An area the size of New Jersey and Delaware combined has received over 12 inches of rain, with some areas already totally flooded.

usa est precip 082617

Unfortunately, the track of the storm over the next few days remains in the same general area.

AL092017_5day_cone_no_line

Over just the next 24 hours alone many of the areas that already received flooding rains are expected to see much more. The map below shows forecast amounts of 4-8″ in the next day.

nam_namer_024_precip_p24

For more information about how you can help Harvey’s victims, visit http://www.cnn.com/2017/08/25/health/iyw-harvey-how-to-help/index.html, which has links to a number of agencies helping people cope with this disaster.

Inconvenient Realities

I’ve been asked a number of times over the years my thoughts regarding climate change, given my undergraduate degree in meteorology. For a long time, my response was somewhat noncommittal in that although it seemed likely that something was changing, and evidence was increasingly pointing the finger of blame at man, I wasn’t clear on the ramifications of the increase of these greenhouse gases. We do our best to model what the atmosphere is going to do, but on a global scale, who is to say that other factors wouldn’t step in to moderate the worst effects? Truthfully, in college, we did not spend much time on climate studies or on climate change in particular. We were busy learning the “primitive equations” and thermodynamics. Those subjects were hard enough.

But, I was in college in the mid 1990s. In more recent years, evidence of increasing carbon dioxide and other greenhouse gases being tied to the activities of human beings, as well as evidence of a clear global trend toward warmer temperatures, has made ignoring the scientific consensus about climate change truly dangerous not just for future generations but for all of us alive today. Climate change threatens the health and well-being of all of us, not just those living on the coastlines or on islands, or people who will live centuries from now. Whether it is the danger from melting ice and glaciers, coastal flooding and inundation, deadly heat waves, or more common and severe storms, the threat of climate change is real and current.

Undoubtedly, you’ve seen some of the charts showing the evidence of climate change. Two of the most significant are shown here:

1309_consensus-graphic-2015-768px.jpg

This first graphic shows the steep and startling rise in global temperatures in the past century generally, but most dramatically in the past 30 years. Some of the hottest years on record have occurred in the last 10 years.

203_co2-graph-021116.jpeg

(Credit: Vostok ice core data/J.R. Petit et al.; NOAA Mauna Loa CO2 record.)

This second chart shows the global levels of carbon dioxide over the past 400,000 years, sampled from ice cores. As you can see, carbon dioxide levels over the past 400 millennia have never been as high as they are now, and the burning of fossil fuels is by far the most likely reason for this change.

You also no doubt hear that there is some skepticism about climate change, and to be fair, as I mentioned upfront, not everyone is 100% convinced, even in the scientific community, about how the earth will respond as it gets warmer. But although some of the most dire predictions made in the past 30-50 years have yet to happen, we are unambiguously moving toward a future where lands will be flooded, ice will be melted, storms will be more severe, and climates will change. We know this because these things are already happening.

Former Vice President Al Gore’s movie An Inconvenient Truth, made in 2006, set forth in clear images and terms the dangers we all face. It was an excellent movie that I found moving and highly thoughtful. If you haven’t seen it, I strongly recommend it, particularly if you are on the fence about climate change. I am exploring climate change today because this weekend is the release of the sequel to An Inconvenient Truth, entitled An Inconvenient Sequel. This movie talks about the fight against climate change including the creation of the Paris accords signed by nearly every country on Earth, and from which Donald Trump has said he will pull the USA. But it seems that the movie has a hopeful focus, looking at how available and affordable renewable energy has become, and how people, businesses and governments are waking up to the realities and dangers of a changing climate.

Science should not be political. We are all in this together. We truly have (at least as of this writing) no other world to inhabit. So, to protect the health, well-being and environment of you and all those about whom you care as well as everyone else in the world: read, get informed, vote, conserve energy whenever possible, and support scientific research into weather and climate.

For more information about climate change, please visit these sites:

Extreme Heat Happening Now

Yesterday’s post about the dangers of extreme heat couldn’t have been more timely. As was reported in yesterday’s New York Times as well as other media outlets, while most of the country is experiencing hot and humid weather, the western states–particularly Washington, Oregon and California, are suffering through a terrible heat wave. Many areas will see high temperatures around or above 100 degrees. The map below shows forecasted high temperatures for today.

 

The Dangers of Extreme Heat

I really don’t like the heat. To me, hot and humid weather is just about the worst kind of weather there is. Well, maybe 35 degrees with rain is worse. I can remember back in college when I worked as a weather observer and had to get up at 6am to take readings.. one day in January it was just above freezing and raining heavily. That hurt.

But heat can hurt too. Actually, it is really quite dangerous. While the onset of summer is a cause for celebration for many people (think children, teachers, families on vacation, etc.) there are weather-related health concerns that are often overlooked or minimized during this season. Summer storms can bring flooding or tornadoes. Summertime also sees the ever increasing likelihood of tropical storms and hurricanes. Air pollution is at its worst. But often more dangerous, and even more overlooked, is the danger posed by extreme heat. And as climate change threatens to make extreme heat events even more common, it is important to recognize the danger posed by extreme heat, and to know what to do about it.

Heat is among the leading weather-related killers in the United States. Sources differ on just how many people die each year due to heat. According to the National Weather Service, over the last 10 years, on average 97 people have died directly from heat-related causes each year. In 2016, the number of heat-related deaths was just under this average, at 94.  Other sources suggest that as many as 1000 people die each year due to heat, though this higher number likely includes indirect heat-related causes of death, such as asthma or other breathing-related illnesses worsened by heat. Older adults tend to bear the brunt of heat-related illnesses and mortality. The National Weather Service reported in 2016 that of the 94 people who died directly due to heat, 67% of these deaths occurred in individuals age 50 or older.

Heat waves tend to be particularly dangerous. While there is no universal definition of a heat wave, it is generally defined as a longer period (usually 3 or more days) of unusually hot and/or humid weather. The extended period of heat, along with unusually warm nights, are what make them so deadly. One of the worst heat waves in US history occurred in the summer of 1936, when temperatures soared across almost the entire country. Particularly hit hard were the upper plains states, like North and South Dakota, but even New Jersey saw temperatures rise above 110 degrees. Many states have all-time high temperature records still standing from this heat wave.

july1936-temps

Average temperatures during July 1936.  
(Image courtesy of the National Centers for Environmental Information)

What’s so dangerous about the heat? Basically, our bodies are meant to stay right around the same temperature all the time, usually between 97.5 and 99.5 degrees for most people. This is why we shiver when it gets cold and sweat when it gets hot–it’s our body trying to regulate itself. But when it gets too hot and humid, sweating doesn’t cool us down enough. Or, we might lose too much fluid, and salt, from sweating. If the body reaches 107 degrees, organs can fail and death may occur. Heat cramps, heat exhaustion and heat stroke are the three steps of danger in extremely hot conditions. Simple cramping can quickly lead to faintness, nausea, fatigue and headache when heat exhaustion sets in. And if untreated, heat exhaustion can progress to heat stroke, a potentially fatal condition.

And it doesn’t have to be excessively hot to cause health problems. The combination of heat and humidity, often called the heat index or the THI (temperature-humidity index) can have the same effect as heat alone. Even temperatures in the upper 80s can become hazardous if relative humidity levels climb toward 60%, a combination found in many areas in the US in the summer. And any prolonged exposure to high heat is dangerous.

So what should you do when the heat hits? Well, obviously, drink plenty of cool fluids and get inside into the air conditioning. Before air conditioning, though, people often went outside to avoid stifling indoor temperatures. Sleeping outside in screened-in porches was common in the days before air conditioning became ubiquitous in the 1940s. Today, there are many ways to keep cool on hot days including:

  • Staying hydrated, particularly avoiding alcohol and caffeine
  • Eating smaller meals, including those with fruits and vegetables not requiring cooking
  • Using fans, like ceiling or box fans, and
  • Moving to lower levels of buildings, since heat tends to rise

Heat brings to mind summer fun for many of us, and rightly so. But keeping the potential dangers in mind, and how to avoid them, allows us to enjoy more summer days to come.

 

Heat-related bonus fact: Many people know about heat waves. But have you ever heard of a heat burst? This rare meteorological phenomenon occurs when a thunderstorm dies out in an area with warm, dry air aloft. The downdraft from the dying storm can pull down the warm, dry air, which warms as it drops. This can cause a rapid rise in temperature. It is rare and short-lasting but can raise temperatures up to 20 or 30 degrees in just a few minutes!