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Reflecting on the Extent of Human Impacts on this Planet, and on the Need to Act on Climate


Last Sunday our temperature cracked 0oC for the first time in ages. On Tuesday the snow was melting rapidly and the temperature was a balmy 6oC. Yesterday I was out for a walk and came upon a gaggle of about 15 wild turkeys. The women, all dour and pinched-looking were off to one side, clearly gossiping about the men, while the three men had their tails fluffed fully, their necks back and heads up, sizing up each other judiciously with one eye occasionally cocked towards the girls. They at least were thinking about Spring! We are projected to break 0oC through till this Monday and then hover around 0oC for the week. The sun feels warmer than it has in weeks, and we’ve switched the clocks back for daylight saving. Spring is coming at last.

NOAA reports that January was globally the second warmest on record since measurements began, and that Eastern North America was seriously atypical. You can see that abnormality in their map of temperature anomalies (deviations from the average climatic values). The gloating from Vancouver, as they basked in double digit temperatures, could almost be heard here in Ontario, although most people now understand that our savage winter was a result of the warmer Arctic – I just hope this pattern is a temporary one. As is becoming routine, NOAA’s map is mostly a sea of pink and red, because most of the planet was warmer than usual in January. Global sea surface temperature was the warmest ever, confirming, in a way, that warming of the planet has been continuous, even during the so-called warming ‘pause’. The heat has been getting stored in the oceans.

NOAA NCDC Jan 2015 anomalies 201501

The NOAA NCDC map showing extent of deviation from average temperatures across the planet in January 2015, the second-warmest January on record.
Map courtesy NOAA National Climatic Data Center

The Warming Continues, and Heat Can Kill

Fact is, the warming of the planet is as serious as it ever was, quite a bit more serious than people imagined it would be when the IPCC was first getting started in 1988. We really do need to become more excited about the need to act on climate, so to that end let me tell you about three recent assessments. In the January issue of Nature Climate Change, Nikolaos Christidis, Gareth S. Jones and Peter A. Stott of the UK Met Office’s Hadley Centre discussed the problem of hot summers. Heat waves kill people. Even in advanced countries. The European summer of 2003 was the warmest for several hundred years, particularly in France, Germany and Italy, and temperatures exceeded 40oC in some northern French towns. The average summer temperature across Europe that year was 2.3oC warmer than average, and the unusually warm weather took a toll, particularly among the elderly who mostly succumbed in their apartments to heat exhaustion and dehydration. Reliable estimates suggest 70,000 extra deaths occurred across Europe that summer because of the heat.

france-2003 heatwave AFP-Getty

French patients being treated during the 2003 heat wave.
Image © AFP/Getty

With the world becoming warmer, it is logical to assume that the likelihood of a summer comparable to that of 2003 will increase in the future. What Christidis and colleagues asked is ‘how much increase, how fast’. They report that “events that would occur twice a century in the early 2000s are now expected to occur twice a decade. For the more extreme summer observed in 2003, the return time reduces from thousands of years in the late twentieth century to about a hundred years” now (my italics). Using global climate models to peer into the future, they report that a summer like 2003 will be “very common” by 2040 regardless of how we act to address CO2 emissions between now and then. Using IPCC’s RCP8.5, the so-called ‘business-as-usual’ scenario, such a summer will be considered abnormally cold by the end of the century. Of course, by then all the elderly in France will have air conditioning. Or not. The real message is do not let anyone tell you a small increase in global mean temperature is no big deal – it’s a very big deal.

Managing Climate Change in the Mekong Delta

In February’s issue of Nature Climate Change, Alex Smajgl of the Mekong Region Futures Institute, and seven colleagues from Vietnam and Thailand, examine the relative merits of alternative responses to the 30 cm of sea level rise expected in the Mekong delta by 2050.

As well as being home to about 17 million people, the Mekong delta of Vietnam is a low-lying agricultural district in which about half the land (1.8 million hectares) is dedicated to rice production with an annual target of 23 m tonnes. Vietnam’s rice production makes it a major exporter, contributing nearly 20% of world rice trade. This agriculture depends on ample fresh water delivered via monsoon and upstream rain, and a substantial downstream transport of silt (160-200 m tonnes per year). Sea level rise will lead to salt water incursion, eroding the productive rice agriculture. In addition planned changes upstream (both monsoonal changes and new dams for irrigation and hydroelectricity in Laos, and Cambodia as well as Vietnam) are expected to cut the delivery of silt by 50% and further enhance salt water intrusion.

Rice-fields Vietnam Insiders Asia

The rice paddies of the Mekong Delta enable Vietnam to provide 20% of the rice on the world market. Climate change and upstream development actions will require adaptation if this productivity is to be retained. Image © Insiders Asia

The article discusses possible options for dykes and seawalls (at a construction cost of US$ 5-8 billion) as well as what they term soft options – a shift towards more salt-tolerant varieties of rice, other crops and shrimp aquaculture – which are less expensive but require greater change in farming practice and in government policy which currently focuses on rice as an export commodity. The solution is not easy. The community will be resistant to altering patterns of life, and several government ministries are pushing the engineered option despite the cost and likely poor outcome. A rational approach by all parties could be useful – the authors favor a hybrid solution with some engineered protection and some modification of agriculture as the best outcome. Time will tell what will really happen. And this struggle with the ocean will be repeated, with subtle local variations in many other productive coastal regions around the world while governments stretch to cover infrastructure costs and farmers struggle to continue to make enough money from their crops to feed their families.

Thawing of Arctic Permafrost

The January issue of Nature Climate Change contained an article by Ake Nauta of Wageningen University, Netherlands, and 10 colleagues from various Dutch, Danish and Russian institutions. They described a simple field experiment run over five years at a lowland site in north-east Siberia. In a set of five 10m diameter plots they removed all shrub vegetation (chiefly dwarf birch, Betula nana). A set of five control plots were left undisturbed with their shrubby vegetation intact. Nauta and colleagues then tracked changes in the plots over five years.

The issue they were investigating was the way in which presence of above-ground vegetation might modify the way in which permafrost melts as the Arctic warms, and therefore the extent to which tundra sites act as carbon sinks or as carbon sources. Such information is vital if we are to understand and therefore project into the future the pattern of climate change in the Arctic.

At present, the Arctic is warming twice as fast as more temperate localities, and as permafrost melts organic material that has been trapped in the soil begins to decompose, releasing methane to the atmosphere. Such methane releases can become a potent positive feedback mechanism for climate change. Nauta and colleagues found that the experimental and control plots differed significantly within one year. Thawing of the soil during the summer season extended 5 cm deeper into the soil in the denuded plots than in those that still had shrubs present. By year 5, the added depth of annual thaw was 15 cm.

Nauta Fig 2 nclimate2446-f2

Figure 2 from Nauta’s article showing the marked difference in surface profile in the vegetated (control) and the denuded (removal) plots in the final two years of the experiment. The plots all had similar profiles at the start of the five years.
Figure © Nature Climate Change

By year 4, there also was noticeable subsidence in the removal plots, leading to deeper snowpack the following winter, and subsidence was even more pronounced the following year. In other words, the presence of the shrubs protected soils from the full effects of the warming climate and slowed the melting of permafrost. In the absence of shrubs, permafrost melting was more extensive with the result that land became depressed as water left. Measurements of methane flux during the final year of the experiment revealed that methane was being taken up in the control plots, but released to the atmosphere in the denuded plots.

Relative surface elevation, snow depth, groundwater level and methane flux in control and B. nana removal plots in 2012.

Figure 3 showing that, at the end of the experiment, control plots were higher, collected a thinner snow pack, had less water-logged soils, and emitted less methane than plots from which all shrubs had been removed. [The symbols (*), *, and ** denote significance levels of 10%, 5% and 1% respectively.]  Image © Nature Climate Change.

These results reveal that permafrost melting is going to proceed quite differently from place to place as the climate warms. Shrub communities will be particularly important in slowing rates of thaw, and keeping soils functioning as carbon sinks as long as possible. It’s a small study that raises some important big questions about how we manage the ‘desolate’ tundra in coming years. We have realized for some time that the warming of the Arctic is going to be ‘complicated’ and probably ‘problematic’, and this study gives one more detail on how. Nauta and colleages close their article with an observation that expanded oil and gas exploration, or comparable types of mineral development, for example, will tend to reduce or eliminate vulnerable shrub cover, thereby worsening the rates of permafrost thaw and rates of methane emission from soils. I don’t think that thought has been part of Stephen Harper’s reflections over how Canada will benefit from climate change by ‘opening up’ the Arctic.

The Extent of Human Impacts on our Planet

If anyone still doubted it, we really must move on climate change mitigation. The old argument that the change is not likely to be ‘that bad’, or ‘as bad as the scientists are saying’ has now worn very thin. Our news media are full of stories of the latest sign that our world is changing fast, and the current effort among geoscientists to gather the evidence necessary for them to decide whether or not to formally recognize that we have entered the Anthropocene has once more made clear just how radically we have already altered our planet.

An article by Simon Lewis and Mark Maslin of University College London in the 12th March issue of Nature seeks to identify a clear geological marker for the start of the Anthropocene. This is a necessary step towards formal recognition of a new geological period – the specific time-period must be definable by some geological marker. (For example, the end of the Cretaceous is formally defined by a globally distributed thin bed very rich in Iridium, a normally rare element believed produced by an impact by a massive asteroid that was the, or the major, event that triggered the massive changes that occurred at that time.) Among the Anthropocene start dates they consider, some are expected – the start of the industrial revolution in 1750-1800, and the start of the nuclear age with development and a peak of atmospheric testing of bombs between 1945 and 1963. Of these, the industrial revolution has no clear marker for its commencement, while the peak levels of 14C in tree rings and ice core strata from the early 1960s uniquely mark the start of the nuclear age.

To me, a more surprising signal, and one Lewis and Maslin propose for serious consideration as an Anthropocene start date, arises from the European colonization of the Americas. In the period between 1492 and 1650, that colonization led to a collapse of native American populations (from about 60 to 6 million people), and a substantial exchange of new world and old world foodstuffs, as well as some other plants and animals. The first records of pollen of Zea maize (native American corn) in European sediments in 1600 mark this event, but the authors instead turn to a brief reduction and recovery in the concentration of CO2 in the atmosphere, as recorded in ice cores dated to 1570-1620. During that time CO2 concentration fell by 7-10ppm, because the immense dying of the native American population led to a collapse of agriculture in the Americas, and a regrowth of forests. The forests sequestered carbon, removing it from the atmosphere. Their numbers are staggering. About 50 million hectares of forested land regenerated over about 100 years, with a resulting uptake of 5-40 Pg of carbon from the atmosphere (that is 5 to 40 billion tonnes of carbon, 18 to 147 billion tonnes CO2). We currently emit about 10 billion tonnes of carbon per year. Lewis and Maslin suggest this event is a suitable marker for the start of the Anthropocene; to me it is simply one more piece of evidence of how substantively we have been changing this planet, and for how long.

Bradshaw_rock_paintings Wikipedia

Even before these ~50,000 year old Bradshaw images were painted in Australia’s Kimberley region, humans were having measurable effects on this planet, chiefly through our extermination of numerous megafauna. Image from Wikipedia

Lewis and Maslin note other pronounced human impacts on the planet. Our invention early in the 20th century of the Haber–Bosch process, which allows the conversion of atmospheric nitrogen to ammonia for use as fertilizer, has altered the global nitrogen cycle so fundamentally that the nearest equivalent is the evolution of nitrogen fixation by cyanobacteria and the consequent generation of an oxygen-rich atmosphere 2.5 billion years ago. Our release of 555 billion tonnes of carbon into the atmosphere since 1750 has raised the concentration of CO2 in the atmosphere to a level not seen for at least 800,000 and probably several million years, and delayed the planet’s next glaciation event. Those emissions have also set in train changes to ocean pH and sea level that will take hundreds of years to play out. We have appropriated 25-38% of primary production for human use, and taken over some 40% of available land for our use, thereby leading to extinction rates for other species that are 100 to 1000 times more rapid than usual, and may be signaling the start of the sixth mass extinction event. Our invention of novel chemicals such as plastics, antibiotics, and pesticides; our creation of novel genetically modified organisms; and our transport of species around the globe have collectively altered the course of evolution on the planet. Furthermore, the rates of most of these changes, particularly since 1950, probably exceed the rates of change any extant species has experienced in its evolutionary history. And our changes are cumulative and synergistic.

Any Political Progress Yet?

The IPCC expects to receive plans from governments over the next several months, and Switzerland was the first country to comply. Released on 27th February, the Swiss plan is for a reduction of emissions to 50% of its emissions in 1990 by 2030. This will be accomplished by partitioning with 30% achieved within Switzerland and 20% achieved through carbon markets or other offsets (purchasing reductions achieved elsewhere in the world). Switzerland currently emits 0.1% of global CO2 emissions (6.4 tonnes per capita per year) so these planned improvements will not make a huge difference to the overall problem. But they are of appropriate amount if achieved, and Switzerland is behaving responsibly. The Swiss also plan for achieving a 70-85% reduction by 2050.

abbott-harper1Steve Christo-G20 Australia-CC BY-NC-ND

The happy couple? The Bobbsey Twins of Fossil Fuel? Two climate-denying prime ministers?
Photo © Steve Christo/G20 Australia/CC BY-NC-ND

Canada continues to dither while our government tries to strike fear into our hearts – fear of terrorists, fear of pedophiles, fear of environmentalists, fear of science – while ramming bold new initiatives through Parliament to strip away our rights and freedoms in order to protect us. The uncanny parallel in behavior of Stephen Harper and Australia’s Tony Abbott continues, and I remain justified in calling them the Bobbsey twins of fossil fuel. The International Council for Science, more circumspect, dubbed them the ‘climate bad boys’ on its Road to Paris website on Feb 10th. In their words, Australia and Canada are

“two mid-ranking powers —both in the G20, one in the G8—that are not just global warming laggards, but have made sharp u-turns from earlier international pledges, overturned previous governments’ climate legislation and boast leaders that are themselves climate sceptics and have even muzzled climate scientists.”

Neither seems to have ever seen a fossil fuel project he did not like. If there is a glimmer of awakening to the reality around him it is that Harper has now been heard, on at least one occasion, to say that climate change is a major problem. But he did not elaborate, and did not say whether it is a big problem because it interferes with his agenda or because the world needs to do something about it. It seems it is big but not yet major enough to trump such important issues as whether a new Canadian should be permitted to wear the niqab when taking the oath of allegiance. Protecting us from climate change is probably a bigger and more important problem if you measure the economic cost of not acting.

On March 3rd, CTV News reported that Environment Canada has been whispering quietly to Provinces, to find out what plans they have for counteracting climate change. While Harper’s Environmental Minister, Leona Aglukkaq, has refused requests for interviews on the topic over the past month, her spokesperson said,

“Canada is actively preparing its intended nationally determined contribution [to emissions reduction]. As this is a national contribution, the provinces and territories hold many levers for taking action on emissions, so the minister is seeking feedback from her counterparts on how initiatives in their jurisdictions will factor into Canada’s overall commitment.”

No national announcement. No billboards trumpeting how “Your Harper Government’s Climate Action Plan” will somehow help us all become loyal followers in the great greening of Canada. No talk about how our new greener economy will provide high-paying jobs to Canadians while keeping our environment entire. Just some whispering by lowly civil servants at Environment Canada, with the hope that they will be able to stitch together a little bit of BC climate tax, some Ontario expansion of green energy, and some Québecois capping and trading with California to produce a distinctively Canadian climate quilt to be taken to Paris. Just thinking about it makes one so proud to be Canadian. I’m sure Ms Aglukkaq is not talking to the press because she is just overcome with emotion over this grand, inclusive, distinctly Canadian plan being nurtured behind closed doors.

Canadians seem well ahead of their government on climate, but with the Federal government doubling down, keeping the discussion centered on terrorism, law, and order, and with the two main opposition parties still very gingerly stepping around the climate file, Canada is not getting the national political leadership it deserves. A thoughtful piece by UBC’s Max Cameron, in The Tyee on 2nd March provides a clear statement of the political and economic aspects of the climate issue. He addresses the difficulty any democracy faces when attempting long-term change – a difficulty perhaps sharpened in the increasingly polarized political community in Canada and the USA. He also says, very clearly, listen to the scientists, this is a real and growing problem.

As I write this, the prices for gas and oil continue to erode, and exploration in the tar sands grinds to a halt. Those corporations that have told us repeatedly in their airbrushed commercials how much they care about Canadians, are cutting back any activities that are not providing profit at the present time. Turns out all those great jobs we’ve been told about can be terminated with little notice, and they are now disappearing. The Alberta economy is tanking once again. Now, when gasoline prices are low, is the very best time for a national carbon tax, and Canada should put one in place. A national price on carbon is infinitely preferable to a patchwork quilt of measures put in place within single provinces (although full credit to provinces like British Columbia that stepped up to partly fill the national vacuum). The revenues from a carbon tax can be split, with a portion used to subsidize less well-off individuals facing added living costs, and the rest used to subsidize the cost of transition towards greener energy and the cost of adaptation to the environmental impacts of climate change.

We need a government that sets priorities that favor a shift away from fossil fuels as quickly as possible. What we have is a government (and a good portion of the opposition) that is starting to talk about mitigating climate change, while continuing to advocate expanded use of the tar sands. Having it both ways sometimes works in politics, but not this time. As Tim Gray of Environmental Defense said of the tar sands in an Op-Ed in The Star on 25th February,

“To be clear, we’re not saying shut it down today. But there should be a moratorium on new projects and pipelines until Canada has meaningful policies and actions in place to address carbon emissions.

“There may be a future where some tar sands oil can be extracted while we reduce overall Canadian emissions. Such a future would also involve cleaning up extraction-related local impacts, negotiating fairly with affected First Nations, undertaking deep de-carbonization of the electricity grid (including closing Alberta’s coal-fired electricity plants), making massive investments in electrifying transportation (Ontario’s big polluter), scaling up energy conservation programs for industry and buildings (a huge opportunity in Quebec) and investing in new technologies that will create wealth and reduce emissions.

“This is actually a possible future for Canada and one that would help increase the productivity of industry, spur innovation, reduce costs and enhance our quality of life. Other countries are waking up to this possibility, investing in the clean economy and making public policy to enable it. Canada is not and we’re at risk of being left behind.”

To which I can only add, Amen. And immediately note that, as I write, Vanuatu is being hammered by Category 5 cyclone Pam, with 270 km/hr winds, causing massive destruction on this remote, vulnerable island nation, home to just 267,000 people. It is the worst storm there in recent history. Sure, we cannot claim this storm is a consequence of our changing climate, but the world is seeing far more ‘worst ever’ events these days. If we actually care about our own, and our children’s lives, we will act on climate now.

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