Summary: Dr. Robert Kopp explains why humans die in heat waves, and why that will get worse as climate change develops. Then the incredible Dr. Jeremy Leggett on “Winning the Carbon War” Plus climate music from Melody Sheep. Radio Ecoshock 150624.

Welcome back to Radio Ecoshock. I’m Alex Smith with two powerful interviews for you. First Dr. Robert Kopp explains why humans die in heat waves, and why that will get worse as climate change develops. Then the incredible Dr. Jeremy Leggett returns, talking about his open source book “Winning the Carbon War”, his booming solar business in the UK, and a project to light up Africa with solar lanterns. All that plus two climate songs.

Let’s get going.

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Are we making a world where it will be too hot to go outside? Is the latest deadly heat wave in India a sign?

We’ll talk about all that and more with out next guest, scientist Robert Kopp. He’s an associate professor in the Department of Earth & Planetary Sciences at Rutgers University in New Jersey. He’s Associate Director of the Rutgers Energy Institute. He was an author in the Fifth Assessment Report from the Intergovernmental Panel on Climate Change.

Dr. Kopp is also a co-author of a thought-provoking op-ed in the New York Times, published June 7th. The title is “The Deadly Combination of Heat and Humidity“. That was spurred by the massive heat wave that had just hit India, killing hundreds. It might just as easily have been written about the new deadly heatwave that struck this week in Pakistan, leading to more heat deaths. Read about that event, where the “wet bulb temperature” was over 33 degrees C. – in Robert Scribbler’s blog here.

You can find Bob Kopps technical notes to the New York Times article on heat, humidity and climate deaths here.


Radio Ecoshock guest Dr. Jeff Masters also has a related post on India heat wave deaths here. Jeff Masters on the end of this heat wave, here. Jeff writes: “According to the India Meteorological Department, a warming climate increased heat waves in India by a third between 1961 to 2010.” The source for that statement, with more data on deadly Indian heat waves, is here. You can also check out this study “Intensification of future severe heat waves in India and their effect on heat stress and mortality” Kamal Kumar Murari et al, published August 9, 2014.


The key fact Kopp raises is one we understand physically, but poorly intellectually. We all know heat feels worse when it’s humid, or muggy as we say. What happens in the body to make humid heat more dangerous?

Yesterday here in Western Canada it was 101 degrees in the shade, or 38 degrees Centigrade – pretty hot for mid-June. I was still out gardening, because it’s very dry here, a semi-desert. I did not understand until I read that New York times article that a lower temperature, with high humidity, might actually be more dangerous than a hotter drier day. How can we communicate this better?

Canadian weather forecasters try to combine heat and humidity into something called the “Humidex Index”. I think we need a better word to get the public to understand this danger.

It’s not just India or Pakistan. It’s Australia, Siberia, Brazil – and the United States.


In the U.S., in the New York Times, the article says:

In work one of us (Robert Kopp) led for the Risky Business Project, we found that over the period from 1981 to 2010, the average American experienced about four dangerously humid days, with wet-bulb temperatures exceeding 80 degrees. By 2030, that level is expected to more than double, to about 10 days per summer. Manhattanites are expected to experience nearly seven uncomfortably muggy weeks in a typical summer, with wet-bulb temperatures exceeding 74 degrees, about as many as residents of Washington have experienced recently.

Kopp adds in the technical notes:

These results come from the forthcoming book Economic Risks of Climate Change: An American Prospectus, much of the text of which is available as a report at “

“Some summers would have days so stiflingly muggy that a healthy individual would suffer heat stroke in less than an hour of moderate, shaded activity outside.

These stiflingly muggy days are Category IV (‘extraordinarily dangerous’) on the ACP Humid Heat Stroke Index, with wet-bulb temperatures exceeding 92°F. Such days have no precedent in U.S. history. In the ACP analysis, they are expected with 6%/year probability in Illinois and 1%/year probability in New Jersey under RCP 8.5 in 2040-2059. By 2080-2099, 4 such days are expected per summer in Illinois and 1 such day in New Jersey. The average American is expected to experience such a day with 1%/year probability in 2040-2059 and 80%/year probability in 2080-2099.

About an hour of shaded, 150-watt activity at a wet-bulb temperature of 92°F leads to skin temperatures of 100°F and core body temperatures of 104°F (the threshold for heat stroke), based on a Danish study conducted on twelve trained, male endurance athletes, ages 23–34. 150 watts corresponds to ‘moderate effort’ on a stationary bike – about 40% of maximal aerobic capacity for these individuals. The athletes, dressed only in swim trunks and shoes, were asked to pedal to exhaustion on a stationary bike in a room with an air temperature of 95°F and relative humidity of 87%, corresponding to a wet-bulb temperature of about 91°F. After 45 ± 3 minutes of exercise without acclimation, or 52 ± 2 minutes with acclimation, these individuals reached exhaustion and a core temperature of 103.8 ± 0.2°F.


And carrying on this way through the 22nd century locks in a trajectory where summer outdoor conditions could become physiologically intolerable for humans and livestock in the eastern United States — and in regions currently home to more than half the planet’s population.

This remark is based upon a 2010 paper Matt co-authored with Steven Sherwood. This study found that conditions physiologically intolerable for humans (conservatively defined there as areas with peak wet-bulb temperatures exceeding 95°F during the peak of the summer, well into ACP Category IV, and well beyond the current planetary experience) cover regions home to more than half the planet’s population with about 11°C (20°F) of global warming. The regions affected include much of the eastern U.S., China, India, Brazil, and north Africa. Based on simulations with the MAGICC simple climate model, as run for the ACP, such conditions have about a 20% chance of being realized by 2200 under RCP 8.5.”

But this is not yet locked in, Kopp says, if we take greatly reduced emissions pathways.


Since we can’t avoid it now, we must make our communities more resilient to heat and humidity extremes. One step is to expand access to air-conditioning for those who can’t afford it. We must also improve cooling in stiflingly hot factories and warehouses, strengthen public health systems, improve public warnings when heat and humidity are dangerously high, and be willing to shift outdoor work schedules.

There are some additional options we didn’t have space to mention here. These include technologies for passively cooling buildings and urban areas, such as cool roofs and pavements, as well as the broader set of energy efficiency measures to reduce the need for active cooling.

Cool roofs and pavements link here.

Dr. Kopp told us on Radio Ecoshock:

In the second half of this century that’s where we really the effects of changes in greenhouse gases that we start making today. So if we continue on with a fossil fuel intensive growth trajectory, the average American might be experiencing around 17 dangerously humid days in a typical summer in the 2050’s.

Bob Kopp also did background analysis that lead to the breakthrough report called “Risky Business“, launched by luminaries like Hank Paulson and Michael Bloomberg. The report warned of the economic costs of climate change.

Along those lines, I ran into an new Australian study that found even indoor office workers, who presumably have air-conditioning at work, become a billion dollars less productive during heat waves – because their sleep is disturbed during hot nights. We talk about what hot humid weather really means in terms of worker productivity in a hotter world.

I also find it interesting the electric grid is also less productive during heat waves. It takes more power just to cool electric generating plants, and the actual grid is less efficient. Kopp notes that nuclear plants sometimes have to shut down during heat waves (just as millions of people are cranking up their air-conditioners) – because nuclear power plants cannot operate if their cooling water (often drawn from rivers or lakes) is too hot. The same limitations can apply to coal power plants which also have to cool their operations.

In a radio interview on WHYY radio in Philadelphia, Kopp talked about many risks that could be assigned a dollar value, easily understood by business. Then he said there are risks that cannot be expressed economically, but still keep him up some nights. That’s in this Radio Ecoshock interview.

Listen to that Bob Kopp interview on Whyy audio, July 1, 2014, with Kate Gordon, Executive Director of the Risky Business project, on the RadioTimes show with Marty Moss-Coane, here.

Despite all this, Bob Kopp is not a total doomer, thinking it’s all over. We discuss how we can cope with this climate mess, now that we have changed Earth’s primary systems. Part of the problem, which Kopp outlines in his work, is climate change impacts vary from region to region, while the solutions need to be global. This adds a stumbling block to faster action. I may be experiencing a heat wave, just as you are thinking it’s cooler than normal where you live. It’s hard to get us all motivated at the same time.

Bob Kopp did his PHD thesis on the opposite world – the time where the planet nearly froze over. He tells us about “Snowball Earth“, and how close we came to extinction of life at that time, about 650 million years ago. And yet life on Earth came back with a roar, as the first multicellular organisms appeared. It was so prolific of species, the time was called “The Cambrian Explosion” I suppose it’s comforting to know that so far life systems can recover from climate catastrophes, even if most of the known species die off (likely including us in the worst case scenario).

However, Bob Kopp studied another snowball Earth that happened much earlier in the planet’s history. The’Paleoproterozoic Snowball Earth’was about 2.3 billion years ago.

Find out more about Dr. Bob Kopp at

Listen to or download this interview with Dr. Robert Kopp in CD Quality or Lo-Fi


After we visit with out second guest, Jeremy Leggett, I’ve got more critical information for you about heat, humidity, and human deaths. Then we can look into a new weather development where storms get stronger, not weaker, as they move over land. It’s called the “brown ocean” effect.

Before we do that, let’s get in a quick bit of music that is spreading into classrooms and chat rooms around the world. It’s a technique of using a kind of hip rap to communicate science. The band calls themselves “The Melody Sheep” and you can find their series called “Symphony of Science” on You tube.

This piece is titled “Our Biggest Challenge”. It’s a climate change music video, posted on You tube September 12, 2012, with more than 600,000 views so far.

You can download the radio version here.

“Melodysheep is John D. Boswell, creator of the acclaimed Symphony of Science music video series and other viral web videos, as well as a host of unique audiovisual projects. His webby award winning work has been featured on CNN, NPR, Wired, Adult Swim and more.”


He’s been involved in the climate battle for decades. Jeremy Leggett founded the business SolarCentury, and the charity SolarAid. He’s Chair of Carbon Tracker, and author of many books on climate, energy and society. Until recently, Leggett felt what we all feel, that the fight to decarbonize, -to save the planet, – is being lost. Now his web site bears the banner “The Winning of the Carbon War”.

It’s a pleasure to welcome back one of our more popular Radio Ecoshock guests, Jeremy Leggett.

There was a time, way back when, that as an Earth scientist Leggett did research for the biggest oil companies. Then, worried about what he found, Jeremy started writing reports for Greenpeace. I remember in the mid and late 1990’s, Jeremy brazenly told big oil they should stop looking for new reserves, because the deteriorating climate meant they could never be burned. He was way ahead of the game before the more recent pronouncements of unburnable carbon and “stranded assets“.

As you’ll hear in the interview, Jeremy Leggett went into a different kind of climate activism. He established a solar business in Britain, which isn’t known for it’s long sunny days. It’s been a success, and gone international. Leggett tells us his firm Solar Century did over 200 million pounds of business last year, and is financially stable. That’s quite an accomplishment, and it means a lot more renewable energy in Europe and abroad.

Solar Century takes 5% of it’s profits to create a charity called SolarAid. That charity has distributed millions of subsidized affordable solar lights in Africa. There are homes where students can study in the evening, and mothers can see to cook, because of SolarAid. It’s a super vision.

Through all this, I’ve seen Jeremy keep a catalog of the most important news in energy, climate change, and the environment generally. He published it for years on his site, as the “Triple Crunch Blog”. Now Leggett has taken that skill, plus about 5 hours out of every day, to collect the signs that we may finally be winning the war against depending on carbon emitting technology. Those first voices are becoming a chorus of demands for action, and real solutions, around the world. You and I may miss those signs, thinking we are stupidly going down with the carbon ship, but Leggett has moved from deep pessimism to possible optimism.

That reporting coming out monthly on his web site. These are really chapters in his upcoming new book titled “Winning the Carbon War”. It’s an inspiring combination of journalism and open publication of a book as it develops. The final chapter, he tells us, will be written at the end of 2015, after the Paris Climate talks.

Here’s an easy to digest article about this new book.

We are at a pivotal moment in the history of this civilization. Leggett says it is still possible for humans to wreck our whole system, with something crazy like a major war. But except for such a major intervention, we may already be on a path toward saving ourselves from utter climate disaster. That’s as good as optimism gets these days.

Listen to or download this interview with Dr. Jeremy Leggett in CD Quality or Lo-Fi


Let’s get back to what we need to know to prevent heat deaths, or at least some of them. The essential concept is supposedly easy, but I have a hard time wrapping my mind around it. Perhaps it’s because the “wet bulb measurement” adds a new dimension to thinking about temperature.

Temperature is easy, whether you think in Fahrenheit or Celsius. Bigger numbers are hotter. But when we add the dimension of humidity, a bigger number is not necessarily more deadly. It could be 100 degrees Fahrenheit, or 38 degrees C – but if it’s dry, humans can still sweat and cool themselves.

But if we take a common thermometer, mercury in a glass tube, and wrap wet material around the bulb – the essential result is: at what temperature does that wetness evaporate, or conversely, take in even more water from the surrounding atmosphere. That temperature/humidity ratio is called “the wet bulb temperature”, but confusingly, it’s also called “the dew point”.

What is a dew point? Wikipedia defines it this way, quote:

The dew point is the temperature at which the water vapor in a sample of air at constant barometric pressure condenses into liquid water at the same rate at which it evaporates. At temperatures below the dew point, water will leave the air. The condensed water is called dew when it forms on a solid surface.

Our interview with Dr. Kopp makes this clearer with some examples. A dew point of 86 degrees or above, he says, is dangerous for human health, especially for more vulnerable people like the elderly, babies, and people with certain medical conditions. It’s not safe to work outside, doing strenuous tasks, if the dew point is 86 degrees or more.

How high can it go? Again, Wiki says this, quote:

A dew point of 91 °F (33 °C) was observed at 2:00 pm on July 12, 1987, in Melbourne, Florida. A dew point of 90 °F (32 °C) has been observed in the United States on at least two occasions: Appleton, Wisconsin, at 5:00 p.m. on July 13, 1995, and New Orleans Naval Air Station at 5:00 p.m. on July 30, 1987. A dew point of 95 °F (35 °C) was observed at Dhahran, Saudi Arabia, at 3:00 p.m. on July 8, 2003. Dew points this high are extremely rare occurrences.

The very high dew point reading in Wisconsin in 1995 co-incides with the infamous Chicago Heat Wave that killed at least 750 people. I recall the city of Chicago morgue was overwhelmed, and had to bring in refrigeration trucks to stack the bodies. Note that the wet bulb temperature in the recent heat wave in Pakistan was a punishing 93 degrees F.

We already know from climate science that the world is getting hotter, and the atmosphere is getting wetter. Warmer air holds more water vapor. In general, the world’s atmosphere contains about 7% more water now than it did in 1970. That’s a huge amount, almost oceans of water, running through the air. In some cases it forms “atmospheric rivers”. If those coincide with a heat wave, deaths of unprotected, uncooled humans will result.

We all need to learn this, and learn the numbers, whether it’s called “wet bulb temperature”, “humidex” or “dew point” – weather forecasters, city authorities, and citizens will need to really grasp this increasing threat with climate change.


More and more, we are finding that climate change develops into new phenomenon not seen before. These are seldom good. That’s why some prefer the term “climate disruption” for this transition into a different climate.

The novelty of these discoveries means we all need to become students again, no matter how old we are, or what our profession might be. Here’s another one, courtesy of NASA, the U.S. The National Aeronautics and Space Administration. It’s called the Brown Ocean effect. I owe our Radio Ecoshock guest Robert Marston Fanney a tip of the hat for bringing this to all our attention, in his entry in Robert Scribbler’s Blog.

Here’s my understanding of this new thing. In our experience of storms of the last century, in the 1900’s, any hurricane, typhoon, or cyclone tended to pick up extra energy from a warm ocean, and then lose strength as it passed over land. There was less water over land to add energy through evaporation. All weather forecasts took this sort of law of storms for granted.

Now, in a climate changed world, that may not happen. NASA tells us that if certain conditions are met, storms may now keep their strength over land, or even get stronger.

Here is what NASA said in a study in 2013:

A Brown Ocean environment consists of three observable conditions. First, the lower level of the atmosphere mimics a tropical atmosphere with minimal variation in temperature. Second, soils in the vicinity of the storms need to contain ample moisture. Finally, evaporation of the soil moisture releases latent heat, which the team found must measure at least 70 watts averaged per square meter. For comparison, the latent heat flux from the ocean averages about 200 watts per square meter.”

So the wet land acts like a watery energy source, like a “brown ocean”.

Let’s go to a concrete example. There was a lot of concern that the most recent Tropical storm to hit Texas, named “Bill”, might meet these conditions. Texas and Oklahoma had just been slammed with record rains and flooding. There was lots of water left on and in the ground. Would “Bill” pick up strength as it headed inland? In this case, it appears that did not happen. NASA has documented such “Brown Ocean” cases, with the best known storm happening in Texas and the central states in 2007. In fact, there have been 16 cases where tropical cyclones kept their power, or increased it, while travelling over land.

NASA also expects more brown ocean events as climate change develops. That turns storm forecasting on it’s head. What used to weaken over land, can maintain it’s destructive power, or get even worse. It’s another development in our understanding of extreme weather events, in an era of human-induced climate change. You’ll hear more about violent storms that won’t quit, even if the weather person on TV doesn’t tell you why.


I don’t know if this will be the hottest June the human world has ever recorded. It sure feels like it here, where the temperature soars over 100 degrees, or 38 degrees Celsius, day after day, in what should be the Canadian spring. The fact that the El Nino hot water system in the Pacific has not declined probably aids our journey to another record hot year in 2015. Somehow that Southern and Central Pacific hot water seems to have split into a new hot blob of water off the coast of the Pacific Northwest. It’s amazing. The rainy city of Vancouver Canada just had it’s driest month of May ever. June is hot and dry. It’s like San Diego moved way north.

That’s why I’m reviewing Marjory Wildcraft’s You tube video on gardening in hot weather. I’m hoping next year to begin some experiments of my own in cooling and adapting a garden for extreme climate change. Marjory is way ahead of us on that, and I hope to get her back to talk about ways to prepare your food production for extreme climate change.

We close out this program with one of my new songs, called “Step Out”. It calls us all to move away from screens and tiny rooms, to get outside.


Now that the Pope is saying what I and my guests have been saying for 8 years, is it time to retire? Not likely. But next week will be my last of the regular season. I produce 45 new shows a year, starting in September and running straight through until the end of June.

During the summer, I work through our archives, to find the key interviews many of you may have missed. There will be a “best of Radio Ecoshock” every week.

One more new show to go though. Stay tuned!


Radio Ecoshock