070 Polar bears and climate change denial, Alberta’s mountains see the highest temperature increases and did European contact in the New World cause the Little Ice Age

Polar Bears and climate change

In this episode, I look at polar bear ecology and how they have become a pivotal tool in the work of climate change deniers. I also investigate that despite almost half of Albertans denying that climate change is real, it has seen significant increases over the past 50 years. Finally, I look at a study suggesting that the arrival of the Spanish in the New World may have caused the Little Ice age.

As a naturalist and guide, I spend my year travelling between the Canadian Rockies and the sub-arctic landscapes of Churchill, Manitoba. When it comes to changing climates, these are two of Canada’s primary battlefronts. In the mountains we are seeing our glaciers disappear at ever-increasing speeds and in Churchill, the bears are constantly dealing with shorter feeding seasons due to warming temperatures.

When we talk about polar bears, we talk a lot about steadily decreasing amount of sea ice available for them to hunt ring and bearded seals in places like Hudson Bay. According to a 2015 study by the Government of Canada, sea ice in the Canadian Arctic has declined at a rate of 6.8% per decade.

In places like Churchill, we often forget that the ice is critical, but it’s also just one of many potential challenges polar bears face. To really understand the situation, I like to refer to the Arctic ecosystem as an ecological Jenga game. If you’re not familiar with Jenga, it’s a game where you stack up a tower of sticks and then pull them out one by one until the tower collapses.

Ecosystems are kind of like that. In the case of the Arctic ecosystem, each of those sticks may represent different components of the ecosystem.

Before we get too far ahead of ourselves, though, let’s ask a basic question; why are the polar bears on the ice in the first place? While this may seem like an obvious question, it also leads us down a rabbit hole of numerous interconnected ecological components.

The bears hunt ringed and bearded seals. These seals also require pack ice to survive. Unlike some seals which thrive in open water, ringed and bearded seals rely on pack ice to provide a stable platform for their birthing dens. It also gives them access to their important feeding areas.

Arctic ice has another really critical purpose. Across the north, there are actually three kinds of ice: multi-year ice, annual pack ice, and land-fast ice.

Multi-year ice is thick and dense. This means that very little sunlight is able to penetrate through the ice to the water below. Without light, there isn’t very much in the way of food in these areas.

Annual pack ice and land-fast ice melt each year. When it forms, it’s much thinner, allowing plenty of sunlight to reach the seawater beneath. The light allows an entire ecosystem to emerge. This sunlight allows tiny algae to grow which in turn is fed upon by tiny crustaceans and copepods.

These provide food for fish like arctic cod which, in turn, provide food for seals. All of these things need to happen before there are any seals for bears to feed upon. If any of these critical layers on this ecological food pyramid are lost, the entire ecosystem may collapse.

Too often, we focus on just one of the many dominos in the arctic and sub-arctic ecosystem – sea ice. What dangers might threaten undersea ecology? Ocean acidification is one major one.

Increased carbon dioxide in the air is also reflected in ocean water. As sea waters absorb more carbon, they become more acidic. Acidification can hinder the ability of some of the tiny crustaceans to form their protective shells and can lead to a population collapse. Without these foundations of the ecosystem, there is no fish for seals to eat and thus no seals, and conversely, no bears.

Already, ocean waters have seen an increase of 30% in acidity since the start of the Industrial Revolution.

We need to look at the entire Arctic and subarctic ecosystem as a whole. Greenhouse gases have far more impacts than simply reduced ice cover. If we find ourselves in a world where there may still be enough ice for bears and seals to survive, but the undersea food supply dwindles due to acidification than we still have a problem. With fewer seals competing for less food, the shortage would be passed on to the polar bears. If there are fewer seals to eat and those seals are smaller due to food shortages, than there will be fewer bears and they will also be calorie poor.

According to a recent study by Polar Bears International, in 2018 arctic ice reached its annual maximum on March 17th, and it was the second lowest maximum ice level on record – second only to 2017.

As they put it in their report:

“To put this in context, this year’s area of missing ice was more than 1.5 times larger than the state of Texas – or 1.16 million km2 (448,000 mi2) below the 1998-2010 average (15.64 million km2/6.04 million mi2). What’s more, the four lowest maximums in the satellite record have all occurred in the last four years.”

While it’s important for bears to have access to the ice of Hudson Bay as early as possible, the timing of its spring melt has an even bigger impact on polar bears. In particular, early melts can have a disproportionate impact on the survival of new cubs, sub-adults, and bears over 20 years old.

With the Hudson Bay polar bears being the most southerly populations, they are one of the first to feel the pinch of shorter hunting seasons. In 1987, the western Hudson Bay population was estimated to be 1,200 bears. By 2011 they had dropped to 806 and in 2016 there were only 780 bears left. That’s a drop of 35 percent in just 30 years.

Biologists are seeing fewer yearlings around the Bay even though the number of cubs has remained the same. This implies that fewer of those cubs are surviving that first year.

On another front, polar bears, which have become synonymous with climate change have come under attack by numerous climate change denial groups. It’s become especially important that when you read media today that you question the source. I’ve seen numerous national news stories attributed to biologists like Susan Crockford of the blog Polar Bear Science. Unfortunately, there is very little science on this blog.

A new study published in 2018 looked at how polar bears have attracted the attention of these blogs and how they distort the science to sell the falsehood that polar bears are doing just fine.

Polar bears are beautiful and iconic animals. They are also a real keystone species of the arctic landscape. Photographs of starving or dead polar bears get a lot of media attention, and not always for the right reasons.

The logic used by climate denial blogs works on the premise that if polar bears are dying than climate change must be real, and so they would need to accept this fact.

However, if they can sell the fiction that bears are doing just fine, and adapting to longer summers swimmingly, than they can continue to push their fossil fuel agendas.

The report identifies three reasons why websites like these deny that climate change is bad for bears.

1. Since bears cover vast areas, we will never know exactly how many live in a particular area as populations numbers will always necessarily be estimates. Based on this, they can simply reply that since scientists don’t precisely know how many bears are out there then how can they say climate change is negatively affecting them?
2. Some populations are actually growing. This growth though is the result of reduced hunting over time and NOT a result of bears adapting to climate change.
3. Since most appeals regarding polar bears and climate change have been based on emotion, they can simply disregard these “fallacious and annoying arguments.”

Evidence of these emotional appeals is commonplace. Videos like one published by National Geographic last year of a starving polar bear showed the caption: “This is what climate change looks like!” The bear was likely sick or injured and its physical condition had nothing to do with changing climates.

National Geographic later apologized for the video when they realized that it was doing much more harm than good.

Another report titled: Internet Blogs, Polar Bears, and Climate-Change Denial by Proxy in the journal BioScience took an empirical look at how these blogs work to obscure real science. I have a link to the study in the show notes at www.MountainNaturePodcast.com/ep070

It points out that:

“Recent evidence shows that climate-change denial involves a growing labyrinthine network of corporations, conservative foundations, think tanks, and the mainstream media. Facebook, Twitter, and other social media outlets also provide powerful voices in the battle for public opinion, and Internet blogs have become major conduits for disseminating various views on AGW (human-caused global warming).”

The report states that denier blogs “focus their attention on observations that, when taken out of context, they can frame in a way that appears to contradict or downplay the severity of climate impacts. Another strategy is to selectively attack prominent lines of research providing compelling evidence of AGW (human-caused global warming)”

It is this latter point that focuses their attention on polar bears. They look at bears as a key domino in the argument that climate change is real. If they can knock down this domino by selling the falsehood that polar bears are doing just fine, they believe they can use it to knock down all of the other dominos. If one fact is not true then obviously all of the others must be false as well.

The study looked at 90 blogs that mentioned both polar bears and sea ice. The blogs tended to fall on one or the other end of the spectrum with few falling somewhere in the middle. Researchers looked for the sites stated positions based upon the following statements:

1. “sea-ice extent is on average declining rapidly in the Arctic;
2. sea-ice extent is decreasing only marginally, is not decreasing significantly, or is currently recovering in the Arctic;
3. Changes in sea-ice extent in the Arctic are due to natural variability, and it is impossible to predict future conditions;
4. Polar bears are threatened with extinction by present and future AGW (human-caused climate change);
5. Polar bears are not threatened with extinction by present and future AGW (human-caused climate change); and
6. Polar bears will adapt to any future changes in Arctic ice extent whether because of AGW (human-caused global warming) or natural variability.”

They also found every peer-reviewed paper they could find that mentioned the same points, 92 papers in total, and scored then against the same criterion.

When they compared the 45 science-based blogs to the 45 denier blogs, they found each taking very different approaches.

Science-based blogs used convincing arguments based upon peer-reviewed science that showed a clear correlation between human-caused climate change and the threats that it poses to polar bear populations.

Denier blogs focused on remaining uncertainties regarding the effects of global warming, “suggesting that those uncertainties cast doubt on the present and future demographic trends of polar bears.”

Here is one really important statement from the report:

“Approximately 80% of the denier blogs cited here referred to one particular denier blog, Polar Bear Science, by Susan Crockford, as their primary source of discussion and debate on the status of polar bears. Notably, as of this writing, Crockford has neither conducted any original research nor published any articles in the peer-reviewed literature on the effects of sea ice on the population dynamics of polar bears. However, she has published notes and “briefings” through a conservative think tank, the Global Warming Policy Foundation (GWPF), and is described by them as “an expert on polar bear evolution.” Similarly, the Heartland Institute, another conservative think tank that downplays AGW, describes her as “one of the world’s foremost experts on polar bears.” Prominent among blogs giving Crockford’s blog disproportionate attention are Whats’ Up With That? and Climate Depot, suggesting that her blog reaches a large audience.

We need to stress real, peer-reviewed science if we want to educate people on the need to reduce global carbon emissions if we want to continue to share the landscape with animals like polar bears.

This is also why it’s even more critical for scientists to go on the road doing interviews, educating non-academics, and mastering social media in order to make sure that good science gets the headlines. After all, the deniers are already masters at all of these things.

As one of only a few people lucky enough to earn a living showing polar bears to visitors to Churchill, Manitoba, there’s nothing like watching a wild polar bear walk right up to a tundra buggy and look at you through the window.

Polar bears may be just one of a myriad of arctic and subarctic species threatened by climate change, but they are also a symbol of the need to take changing climates seriously.

Albertans deny climate change while seeing some of the biggest temperature increases

A survey published in Oct of 2018 by the Ecofiscal Commission found that when it comes to believe in human-caused global warming, Albertans are the most skeptical of all Canadians.

In the survey, when asked: “Is the Earth Warming?” 61 percent of Canadians agreed that there was scientific proof of human-caused change while only 11% denied this fact.

People were asked to choose one of the following options regarding their belief that the Earth is warming:

1. There is conclusive evidence the Earth is Warming.
2. There is solid evidence to the fact that the Earth is warming
3. There is some but not conclusive evidence.
4. There is little evidence or
5. There is no evidence.

If we combine the responses to questions one and two, 61% of Canadians agreed that the planet is warming while only 52% of Albertans agreed compared to 69% in British Columbia. While Alberta got the worst marks, Manitoba and Saskatchewan had a belief rate of only 53% and Ontario 57%.

Surprisingly, there was a huge disparity across political party lines with 75% of Liberal supporters believing that the planet is warming as opposed to only 45% of Conservatives. The NDP had a rate of 73%.

Clearly, we need to do more to educate Canadians as to the importance of understanding climate change and the human-caused nature of it.

While many Albertans may not believe that the planet is warming, a study published in the journal PLOS.org in January of 2017 shows that the communities of Calgary, Banff, and Jasper are seeing the highest temperature increases in the province.

Researchers Dr. Khan Rubayet Rahaman and Dr. Quazi K. Hassan of the University of Calgary investigated precise temperature measurements between the years 1961 and 2010. They wanted to gain a clearer understanding of which areas of the provinces are warming up and at what rates.

The study showed more than 2/3 of the province has experienced warming of between 1/4 of a degree to more than 1 degree C over that period.

Surprisingly, the areas with the highest local warming were Calgary, Canmore, Banff, Jasper, and Grande Prairie, as well as the northwest portion of the province.

Edmonton only saw an increase of 1/4°C, however, all of Alberta’s other cities saw much larger increases.

This may not sound like much but Alberta is home to 21 ecological sub-regions and all have been impacted by these, As lead researcher Rahaman put it:

“If the temperature shifts even 0.25°C more, there may be problems with agriculture, ecosystems and uprooting of wildlife…”

“This is a warning to adapt now. It’s a wake-up call because there could be something like water stress coming, forest fire, natural disasters, and then agriculture practices will disappear.”

Here are some of the papers key findings:

• Some 68% of the province experienced local warming during the period between 1961 and 2010.
• Cities receiving in excess of 0.75°C warming included Lethbridge, Medicine Hat, Calgary, Red Deer, Grande Prairie, and Fort McMurray.
• Rocky Mountain areas including Banff National Park saw significantly higher warming than most other areas, with some areas showing increases in excess of 1°C.
• Globally, the average increase is only 0.28°C. Nationally, between 1948 and 2009, Canada has seen an increase of 1.4°C.
• The Canadian Prairie Provinces have seen an increase of 0.9 to 1.7°C.

As Canadians, we need to realize that the climate is changing whether or not you believe in global warming. We need to all play a role in talking to each other to spread the word that our temperatures are rising and we need to be planning for those changes down the road.

Did the European Arrival in the New World Cause the Little Ice Age?

Anyone who spends years exploring the Canadian Rockies will be very aware of the unprecedented rate of melting in our mountain glaciers. Current estimates indicate that by the year 2100, more than 98% of all glaciers south of the Arctic circle will be just a memory.

The most famous of all the glaciers in the Canadian Rockies is, without a doubt, the Athabasca Glacier of the Columbia Icefields in Jasper National Park. The Athabasca can be seen along the world-famous Icefields Parkway, the highway joining the mountain communities of Banff and Jasper, Alberta.

It is one of the most scenic corridors in North America and one of the main attractions has always been the plentiful number of glaciers visible along its 230 km or 140 miles of mountain vistas.

The Athabasca Glacier, while only one of the six major glaciers flowing off of the Columbia Icefields is by far the most visible, and consequently, the most studied glacier in Canada. Glaciologists and climatologists have long used the changes reflected in this one glacier to help them to understand similar changes being seen across the mountain west.

Without exception, the glaciers are shrinking at a dramatic rate…but that wasn’t always the case. When the first explorers, fur traders, and mountain climbers first wandered the mountain landscapes, they saw very different scenery. The glaciers were vastly larger than they are now and covered much more of the mountain landscape. When looking at old images of the Athabasca from the date of its discovery in 1898, today is it just a tiny remnant of its former glory.

In the 1840s, had any cameras been around to photograph it, this river of ice spread all the way across the current highway up to the base of Mount Wilcox behind the Columbia Icefields Chalet. And not only was it longer, but it spread all the way across the valley into which it now looks insignificant in comparison.

This moment of glacial history represented the end of a period known as the Little Ice Age. While the name may undersell its significance, there was nothing little about the Little Ice Age. It represented the single greatest advance of glacial ice in the previous 10,000 years, since the end of the great age of glaciers.

This period of global cooling wrought havoc across Europe with cold weather causing crop failures and starvation at times. While the cooling first began around 1315, it led to political instability and starvation in places that had previously been wealthy.

Others blamed the black death or bubonic plague on these early cold spells. During the 14th century, up to 60% of Europe’s population died resulting in some 75 million deaths.

Shortly before Columbus sailed to the new world, and enters today’s story, Pope Innocent VII began to blame witches on the cold and led to the witch trials across Europe and eventually in the New World as well.

A new study published in December of 2018 in the publication Quaternary Science Reviews investigates whether the deaths of more than 50 million indigenous peoples of the New World may have had a hand in making the Little Ice Age just a little icier.

The basic premise is that prior to Europeans arriving in the New World in 1492, the Americas were already very heavily peopled with numerous indigenous peoples, including the Mayans, Incans, Aztec, Amazonian peoples, and the native tribes of North America.

As the white men arrived, along with them came diseases with eventually wiped out 98% of all these ancient peoples. As these people died, so did the intense agriculture that had been a mainstay of new world culture for centuries.

As fields were abandoned for lack of people to maintain them, forest regrew and absorbed vast amounts of carbon from the atmosphere. With the uptake of carbon, global temperatures would have fallen in response.

If there is one aspect of the current story of changing climates and warming temperatures that is critical, it’s the understanding that the more carbon in the atmosphere, the hotter the planet is. This study looks into whether this sudden loss of carbon in the global atmosphere may have been responsible for some of the drop in temperature that caused the Little Ice Age.

If this is true then this would have been the first true case of human-caused climate change and strong evidence of how people can have dramatic effects on global climates.

Ok, that’s the elevator pitch, so let’s dig into the meat of this story.

When the Spanish arrived in the Americas in 1492, they didn’t arrive in a ‘new world’ as it is often referred, they arrived in an ancient one, with huge civilizations of people that had spread across North and South America.

While there is still some debate as to how the first immigrants to the Americas arrived (check out Episode 6, where I discuss new challenges to prevailing theories about the first people to arrive in North America, or Episode 37 where I look at a new ancient site on the British Columbia coast that has helped revive the theory of a coastal migration from Asia to the Americas), there is no doubt that by the time of the Spanish arrival in the new world, ancient civilizations were already well established.

What we do know about the peopling of the Americas is that after the arrival of some ancient ancestor between 15,000 and 20,000 years ago, these migrants quickly took advantage of a vast landscape of fertile lands to spread far and wide across the mountains, plains, river valleys, and jungles.

In time they developed great civilizations including:

• The Maya of southern Mexico, Guatemala, Belize, El Salvador and Honduras.
• the Inca of Peru, Bolivia, Ecuador, southern Columbia, Chile, and parts of NW Argentina,
• The Aztec of central Mexico,
• The many cultures of Amazonia.
• The many first nations groups that covered the present-dayU.S. and Canada. They comprised dozens of nations speaking many languages. These include languages like Iroquoian, Siouan, Haida, Salishan,  Inuit, Algonquian, Athabaskan, Tlingit, among others.

Just how many people made up these vast civilizations may never be truly known. There are a number of techniques archaeologists have used to estimate populations of pre-contact peoples. According to this report,  these include

“the sizes of their armies, number of adult males, census data, tribute records, numbers of buildings, depopulation ratios, and historic clerical chronicles such as the number of baptisms and number of deaths in a community.”

Unfortunately, many of these techniques come with their own problems. In some cases, they are prone to exaggeration by Spanish observers. In others, census records were often only started some time after the original contact with Europeans.

Based on the most reliable data available, the authors of this study have settled on a population of approximately 60.5 million people already established at the time that the first Spanish explorers arrived on the shores of South,  Central and southern North America.

Their next challenge was to estimate just how much land would have been under cultivation when the first European settlers arrived. By this time, they had extensive agricultural settlements growing primarily corn (or maize), sweet potato, cassava, cacao, fruit orchards, and further south, quinoa, peanuts, chilli peppers, and in Amazonia, a relative of modern rice.

Curiously, rice has been domesticated three times in human history, once each in Asia, Africa, and South America. Each of these domesticated species is from the same Genus Oryza. It isn’t however related to the wild rice harvested in Canada which has the scientific Genus Zizania.

The crops of particular civilizations varied based on their locations, landscape, technological sophistication, and growing conditions.

The techniques used by these ancient farmers included extensive terraced fields fed by very advanced systems of dams and irrigation channels. Other cultures relied more on slash and burn farming. Examining the various techniques employed by indigenous peoples, helped researchers to determine how much land would need to be cultivated on a per capita basis to support the estimated 60.5 million inhabitants.

After examining all of the available evidence, they estimated a value of 1.04 ha or 2.6 acres per person for a total of 61.9 ha under cultivation at the time of first contact.

It’s almost impossible to understand the horrible misery that was visited upon these many indigenous groups as wave after wave of European diseases swept through their villages. Usually, when we talk about European diseases affecting first nations populations, we mention Smallpox. It, unfortunately, was only one of a long list of diseases for which the local peoples had no immunity.

Other diseases that arrived with the settlers included measles, influenza, the bubonic plague, and later malaria, diphtheria, typhus, and cholera.

Any one of these plagues would have decimated the local populations, but with them all in successive waves, the results were a total collapse of the indigenous populations.

The report states:

“While most of the other epidemics in history, however, were confined to a single pathogen and typically lasted for less than a decade, the Americas differed in that multiple pathogens caused multiple waves of virgin soil epidemics over more than a century. Those who survived influenza may later have succumbed to smallpox, while those who survived both, may then have caught a later wave of measles. Hence, there were documented disease outbreaks in the Americas that killed 30% of the remaining indigenous population over 50 years after initial contact, i.e. between 1568 CE and 1605 CE. Indeed, high mortality rates from non-endemic diseases within indigenous communities were still common in the mid-1800s. With at least eight major diseases documented (smallpox, influenza, measles, typhus, pneumonia, scarlet fever, malaria and yellow fever), a 30% mortality rate per new arrival – not uncommon for virgin soil epidemics – would result in a depopulation of 95%.”

The term virgin soil epidemic refers to a disease that is introduced into a population lacking any natural immunity. The first plagues hit the Island of Hispaniola in 1497 and soon spread to the mainland where 10s of millions perished.

It took only 50 years or so for smallpox to spread north to New England and north into Canada.  The terrible unrest brought by disease was also complicated by factors such as slavery, warfare, and famine.

As millions perished, millions of hectares of previously cultivated lands were also left to go fallow. Lands modified by the hand of ancient farmers began to regrow as undergrowth and trees began to reclaim the abandoned fields and terraces.

With the regrowth came trees and other plant growth. These plants began to absorb carbon stored on the land. In time, the amount of carbon in the atmosphere also began to drop as more and more was absorbed by rapidly growing vegetation.

Using evidence like charcoal records and pollen analysis, the researchers were able to piece together a puzzle of changing vegetation as formerly cultivated lands were reclaimed by the surrounding forests. At the same time, because slash and burn farming was also no longer happening, less carbon was being released into the atmosphere through fires.

The carbon absorption would have occurred quickly, with many of the sites reclaimed by forests within the first 50-100 years after being abandoned. They estimated that 7.4 Pg (or picograms) of Carbon would have been captured within the first 100 years following contact. A picogram represents one trillionth of a gram and while it sounds like a miniscule measurement, it would have had a dramatic impact on global temperatures.

This translates to a drop in global carbon in the atmosphere by approximately 3.5 ppm (parts per million). This coincides with a drop in the global atmospheric concentration of 7-10 ppm beginning in the 1500s and ending in the early 1600s.

Researchers then used a variety of techniques to determine that the temperature drops characterized by the Little Ice Age were not caused by other factors such as volcanic eruptions reducing the amount of solar radiation hitting the Earth and thus cooling temperatures.

They looked at the volcanic history from the years 1,000-1800 CE to see if other volcanic eruptions could have resulted in similar conditions. They found that of the 40 largest eruptions in the past 2,500 years, only one occurred during the period of 1520-1610. They found that while large volcanic eruptions can result in lower global temperatures, their effects usually dissipate within 2-10 years.

As they crunched all their final numbers, they conclude that 45-65% of the drop in atmospheric CO2 that occurred during the Little Ice Age was the result of land use changes caused by the deaths of millions of indigenous people.

As the report states:

“Overall, the change in a forcing agent (a large abrupt land use change) driving a reduction of atmospheric CO2 (widespread vegetation regrowth), its location (carbon uptake on land), its timing (1520-1610 CE) and its magnitude (7-10 ppm CO2) each fit with the evidence for the impact of the arrival of Europeans in the Americas directly. By summing the impacts about half of the reduction in atmospheric CO2 can be attributed to land use changes following the Great Dying (4.4 ppm of 7-10 ppm CO2 reduction)”

The implications of this study are astounding. Not only does it bring into stark reality the horrifying realities faced by the first nations of the Americas following first contact with Europeans, but it also shows that such a cataclysm likely had dramatic impacts on the global climate. In turn, we see remnants of those changes in the glaciers around us today.

While glaciers like the Athabasca are much smaller today than they were when first photographed at the turn of the 19th century, they were actually much smaller prior to the Little Ice Age allowing them to reclaim their valleys.

Prior to the Little Ice Age, trees grew in places still covered by the remaining ice of the Athabasca. It’s almost incomprehensible to think that the growth of the glaciers in the Canadian Rockies, along with the other many changes that occurred globally during this period may be directly connected to one of the greatest human extinctions on record.

It also shows that humans have impacted global climatic systems in the past, just as we continue to do today as we continue to pump more carbon into the atmosphere.

On one final note, if you love history, I’ve just posted a new video on YouTube that explores an abandoned cold war bunker near the Town of Canmore. It’s a great walk for the whole family but bring a flashlight because it’s pitch black inside. It represents a little bit of cold war history here in the valley and it’s a trail that few locals are even aware of. You can view the video here: https://youtu.be/N1MERpBIRS4