Whereof one cannot speak, thereof one must be silent

When the Canadian Minister of Natural Resources, Joe Oliver, proclaimed this week in an official press conference that our concern for climate change was ‘exaggerated’, the press rightly fell over him. There is a good summary of that controversial event here: http://o.canada.com/2013/04/12/blog-joe-oliver-casts-doubt-on-climate-science-in-defence-of-oilsands/ . Do read it if you missed the hullabaloo.

Joe Oliver has no background in science. He has a law degree and an MBA and then went on to work in investment banking and securities. Read his CV here: http://www.nrcan.gc.ca/media-room/minister/1955.

The only thing I could think of when I was confronted with this last bit of evidence-denying ideological political game playing of our Federal Government was Ludwig Wittgenstein’s last proposition, the title of this post.

Full disclosure: I am not a philosopher, I was educated in earth sciences and those degree programs were woefully lacking in philosophy and history of science, which I only discovered much later. I read bits of Karl Popper’s work, all of Thomas Kuhn’s ‘The structure of scientific revolutions’ and the occasional article here and there, among others about Wittgenstein’s work (by the way, did you know that his brother Paul Wittgenstein lost an arm in WWI and that Maurice Ravel wrote his now-famous piano concerto for the left hand for him?).

Ludwig Wittgenstein’s “Tractatus Logico-Philosophicus” is one of the world’s foremost philosophical works and it consists only of a hefty series of propositions. The book has been sitting around here for a while and I promise I’ll start reading it after I finish writing this post.

Of course, you shouldn’t speak about things that you know nothing about. Scientists find that self-evident. Isn’t that what science is all about? You try to move forward in your little corner of the sciences, you work according to the rigorous principles of the scientific method, you present your results at a conference and your audience says “how do you know”? “what is your evidence?” “why didn’t you think of collecting other samples/data?” etc. It’s intimidating when you’re young and then it becomes a sport that you wallow in. You start to feel confident, you’re on top of the data, you know where your conclusions come from and where your research should be going and you can answer the questions with authority. You’re making progress.

That’s what Pablo Casals, one of the world’s most famous cellists said when he was asked, at age 80, if he was still practicing. Oh yes, he was still practicing. The interviewer asked why, still, after all this fame and at this age, he was still practicing. His answer: “I think I’m making progress”. He hit the nail on the head – and everyone who is passionate about a trade, an art or his or her science, knows what he meant: we practice and practice and we try to make progress, but we never give up practicing.

And we teach our students these principles as well. Just last week, I was the external reader for a BSc-level thesis. The student had done an impressive amount of work but of course there were loose ends. When it was my turn, I started with a question about one of those loose ends. She hesitated a moment and then said “I don’t know”. I was proud of her! No waffle speak, no trying to come up with something that sounds intelligent but has been fabricated just to sound smart, just “I don’t know”.

There it was: “whereof one cannot speak, thereof one must be silent”. My student will do well, she will continue to practice (she has been accepted in an MSc program), she will continue to grow and she will contribute to our understanding of the earth. That’s progress.

Try that, Joe Oliver

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Dear Dr. Johnston, Your Excellency

Your appointment as Governor General of Canada was an excellent choice. You are a person of stellar reputation. As a scientist, I was thrilled that a scientist of your stature was appointed to this office.

During your relatively short term in this Office, you have witnessed the erosion of Canada’s knowledge base (the termination of the Long Form, the closure of PEARL, ELA, air quality and seismic monitoring stations, etc. etc.), accompanied by increasing censorship and muzzling of government scientists. Today, the pages of the website of the National Round Table of Economy and the Environment (http://nrtee-trnee.ca/), of which you were the founding chair (an organization that was eliminated by the current government), were censored by the minister of the environment.

This leaves you in a strange position: you are – in vernacular terms – “the boss” of this government, specifically of the prime minister. Yet the prime minister has silenced you. Surely this is against the law?

Where does this leave you? And where does it leave Canada? How long must Canada endure this onslaught? As you wrote so eloquently in your paragraph on the NRTEE website, the strength of that body was in the belief that cooperation and listening to each other could bring about positive change. And it did. Back then.

The practices of this government, including those of today that silenced you, deny all this.

I ask you to act on behalf of your current position. You are ‘the boss’ of this country. You have a duty to provide leadership and call these people, who obviously have contempt not only for basic democratic values but also for the authority of your office, to order. A gesture from you could mark a beginning, a turning point in what is now a rapid downfall from everything that Canada once stood for.


Elisabeth C. Kosters, PhD


I e-mailed this letter on the same day that I posted it here, and received an answer today, April 3. Here it is in it’s entirety:

On behalf of His Excellency the Right Honourable David Johnston, I am responding to your email below.

Your kind words of support and encouragement are very much appreciated. The Governor General is grateful for the opportunity to serve as The Queen’s representative in Canada and enjoys hearing from Canadians. Thank you for sharing your point of view with His Excellency.

Please accept my best wishes.

Yours sincerely,

Antoine Morin – INFO
Rideau Hall
1 Sussex Drive / 1, promenade Sussex
Ottawa (Ontario) K1A 0A1

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Rise to the challenge: #$5millionforscience

Two weeks ago the Canadian government announced the creation of a Federal office for Religious Freedom. It will cost Canadian tax payers $5 million per year.

Many Canadians, including myself, do not believe this is a good money destination.

Many Canadians, including myself, are very disturbed about our government’s slashing of science funding, the elimination of funding for the Environmental Lakes Area the most blatant example.

So the obvious challenge is to come up with better ways to spend $5 million. And because this blog is about (earth) science, I want to restrict the challenge to geoscientific issues.

Below are my three choices for spending $5 million. What about yours? Can we make this a challenge? Can we crowdsource $5 million for the best project?

1. Bottom Water Formation in the Geologic Past

In 2012 the Council of Canadian Academies (www.scienceadvice.ca) produced a report entitled “40 priority research questions for ocean science in Canada”. It is an important document because it contributes to formulating a national ocean science agenda.

Canada borders three oceans and has a longer coastline than any other country in the world. Yet Canada isn’t a full member of the International Ocean Drilling Program (www.iodp.org, to be renamed International Ocean Discovery Program). Canada participates as a member of the European Consortium for Ocean Drilling and has no more rights to set international ocean science research than any European country, large or small.

It cannot be stressed enough how understanding oceans, past and present, is crucial to improving the understanding of our planet and by extension to being good stewards of our planet. So I would happily give $5 million to a project that addresses a question under the general theme ‘How did the oceans function under past climates?’ This is one of the 40 questions articulated in the CCA report. Understanding the formation of Bottom Water (which oxygenates the deep oceans) in the geologic past is particularly important. Today, Bottom water is formed only along Antarctica and in one location in the North Atlantic. The situation today is one with bath-tub shaped N-S oceans, one continent conveniently occupying the South Pole and that continent is – equally conveniently – completely surrounded by oceans. This situation is very different from e.g. the Ordovician-Silurian, just to name an example.

Bottom Water Formation drives oceanic circulation and thus climate. If we don’t understand Bottom Water Formation now, we can’t really begin to model future climates. So a researcher with a particularly novel project addresses this question can count on my $5 million.

2. Fluid flow in (non)porous media.

This is a pragmatic research topic. The exploding production of unconventional oil and gas has parties digging their trenches and I don’t believe we understand the issues at hand well enough to make any judgements at all. Not only do we not really know how well we can make oil and gas flow through shale, we also don’t understand the exchange between deep and shallow groundwater reservoirs well enough. Clearly this topic needs massive amounts of research as we already know that we have massive reserves and these reserves could well help us bridge the period to a carbon-poor energy future. See my February 16 post.

3. The Sediment Budget of Minas Basin

Minas Basin is the eastern arm of the Bay of Fundy (see my posts of December 13 and 20, 2012). The Bay of Fundy separates Nova Scotia from mainland Canada and Minas Basin separates Nova Scotia’s southern mainland from its northern mainland. I live at the southern tip of Minas Basin in the picturesque town of Wolfville.

Minas Basin has the world’s highest recorded tides. running as much as 18 m tide range. A decent image and write-up is here: http://oceanservice.noaa.gov/education/yos/resource/JetStream/ocean/fundy_max.htmThe narrow passage that separates Minas Basin from the Bay of Fundy is called Minas Passage. It is about 4 km wide. More water goes through this passage twice a day than all major rivers of the world deliver to the sea daily. This is not an urban myth, it’s the documented truth. A very good animation of the tides is at http://www.gio.gc.ca/science/research-recherche/ocean/modelling-modelisation/coastalembayments-cotieresdesbaies/images/minas-3-eng.gif. Go to the bottom of the page

People have thought about generating power from these tides for more than 100 years, most recently since 2005. If you would install hundreds of tidal turbines in Minas Passage, you would reduce the current (about 10 cm/sec max) and that would affect sedimentation. Sedimentation in Minas Basin is poorly understood because the environment is so hostile. The one and only attempt at a sediment budget for Minas Basin was published by Amos and Alfoldi in 1979 (full reference below). That sediment budget estimate is one of the best ‘back of an envelope’ exercises known to mankind, but we really need more precise numbers now. Not only because of the potential effects of tidal power development, but also because of potential changes estuarine dynamics caused by climate change. $5 million would probably answer the question.

So, these are my three choices for spending $5 million Federal dollars. Do you have a better proposal?

Amos, C.L. and T.T. Alfoldi, 1979, The determination of suspended sediment in a macrotidal system using Landsat data. Journal of Sedimentary Petrology v. 49, no. 1, p. 159-17

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Barrier Island Erosion / Sea Level Rise / Transgressive Anthropogenic Sequences /

Thanks to Twitter, I was made aware of a recent US report, entitled “Coastal impact, Adaptation and Vulnerabilities”. A summary of the report is here: http://www.usgs.gov/newsroom/article.asp?ID=3496#.USVxRFc-6OJ.

What caught my attention on that page was the ‘before and after Hurricane Sandy’ photograph of Mantoloking, New Jersey. They are telling images and we have seen a lot of them in the aftermath of hurricane Sandy and other storms. People seemed genuinely surprised at the amount of sand that was moved landwards by the hurricane (in addition to whole buildings that were taken off their foundations and moved about).

These images never cease to amaze me, if only because of the continued dogged persistence by people to build so close to the ocean.

This is not a treatise on barrier island formation. I just use the occasion to share a set of my own photographs.

Hurricane Katrina struck the northern Gulf of Mexico on August 28/29, 2005. One of the key research areas for barrier island erosion is Dauphin Island (Alabama) and the USGS and NOAA (the same two organizations responsible for the above cited report) published excellent imagery of Dauphin Island, showing how the hurricane had moved a whopping amount of sediment from the seaward to the landward side of Dauphin Island.

Hurricane Frederic struck Dauphin Island in September of 1979 and I happened to be lucky enough to be doing field work (including an overflight) 6 months later in March of 1980, more than 25 years before Hurricane Katrina. There is one particularly interesting difference over those 25 years and the next few images illustrate that difference:

Dauphin Island 1980 2005 1

This is an image of part of Dauphin Island shortly after Hurricane Katrina. The wash overs are clearly visible. Note the position of the road: most houses (these are all vacation homes) are located on the landward side of the road.

Dauphin Island 1980 2005 2

This is an image compiled by the USGS, showing differential erosion and accretion on Dauphin Island, as a result of Hurricane Katrina. A transgressive system in action.

Dauphin Island 1980 2005 3

These are two images from my 2 days of field work on Dauphin Island in March of 1980. The aerial photo shows identical wash overs, but note the position of the road with respect to the homes! Most homes are on the seaward side of the road………….. Did the road move? NO! The road stayed in the same location; rather, as a result of a number of hurricanes that affected the island over a period of 25 years, homes were destroyed and moved rebuilt further landward. This is an anthropogenic transgressive system in action! Can we call this an ingredient of the Anthropocene?

The field photo shows the depth of the scour by these hurricane wash overs: the man in the photograph is ca. 6 ft (1.80 m) tall.

I do wish Canada would produce similar systematic reports as well.

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Wrong Question: can fracking be done safely?

August 2021

A lot has changed in 8 years. My position on hydraulic fracturing has changed too. I could delete this post, but I’m not going to do that.

A lot has changed: the climate crisis has deepened and the fracking industry has not done well. There are serious Issues with unsafe wastewater storage, using too much groundwater, and wastewater leaking into aquifers. Fracking requires massive numbers of wells, who don’t tend to have a long life and get abandoned. Regulatory regimes are poor and these wells leak methane. The landscape and ecosystems in a region where fracking takes place are destroyed. I’m no longer in favour of this practice. I will update this post later with renewed statistics on Canadian energy use.


February 12, 2015

I published this post in February 2013. I have continued to add material to it, so the most recent bits of info are at the top of the page: scroll down for the original, which hasn’t been changed.

Dr. David Wheeler (president of Cape Breton University), who headed the Nova Scotia (government-appointed) panel on hydraulic fracturing in 2013-2014, gave an excellent speech to the Maritimes Energy Association. It’s an overview of our current and future energy needs and a plea for a Carbon Tax. He published it on his blog: Embracing a new energy future for Atlantic Canada”. Read it!

January 23, 2015

The King’s County Register published my letter about fracking (in Nova Scotia). Read it here.

Ten days after its publication, I received an envelope in the mail, i.e. it was sent to my home address by regular snail mail. There was no return address. The envelope contained the printed version of my letter, with a lot of comments, many of which are illegible. It’s clear that the sender doesn’t agree with me. That’s fine. But I wonder what kind of mentality this is? Clearly this person knows who I am and where I live (note that my address was not published in the paper) and yet decides to take anonymous action. Weird? Childish? Uneducated? All of that and more. Here is the annotated newspaper cut-out:

Advertiser letter anonymously annotated

January 6, 2015

Today I read this excellent objective overview of the State of the Art of hydraulic fracturing – I urge you to read it too. It didn’t change my position as outlined below in my original post.


Original February 2013 Post

Yesterday the Province of New Brunswick announced a new set of regulations pertaining to hydraulic fracturing, commonly known as fracking. A summary of these new rules is here

The host of CBC’s Maritime Noon, Normalee MacLeod, paid attention to this news and asked listeners to react to the question that is the title of this post: can fracking be done safely?

I think that question needs rephrasing.

How about this: “Can we develop hydraulic fracturing of shale gas reserves in a way that is safe for people and the environment?”

I want to rephrase the question because I believe we need to regain ownership of this subject. Most citizens – that is: most vocal citizens – are concerned or opposed to shale gas development and the issued is perceived to be one that’s owned by government and industry and citizens seem to have lost faith in both (at least to some extent, because when the pulp and paper industry imploded, citizens expected the government to bail them out; isn’t that a little opportunistic?).

How did we get here? Why is not everyone deeply involved in trying to be part of changing and regaining control of our energy supplies in order to diminish environmental damage and improve the economic balance? How is it possible that most people have at least some concern about global warming and sea level rise, but at the same time are incapable of connecting that concern to their own situation?

First the facts: natural gas is the least dirty of all fossil fuels. The dirtiest one, i.e. the one producing most CO2 (Greenhouse gas, aka GHG) is coal, then oil, then natural gas. Natural gas (methane) is a really bad GHG before it is burned but not afterwards. President Obama has recently made it abundantly clear that the United States is taking climate change serious and he has pledged to reduce emissions. In fact, the US has already reduced emissions seriously these last 5 years – its emissions are down to the level of 1994, thanks to a shift in electricity generation: coal-fired power plants are rapidly being replaced by gas-powered power plants and this shift is made possible by the massive development of shale gas.

“Environmentalists” (I consider myself an environmentalist, but I doubt that those who are labeled environmentalists by the media would agree that I am one) point out that shale gas development has too many unknown risks:

  • potential groundwater contamination by chemicals used in hydraulic fracturing;
  • leakage from wells (both chemicals and natural gas)
  • the combination of the two is a public health risk

These concerns are realistic, but isn’t it our joint responsibility, our duty as citizens of a democratic society to address them and find solutions? Why turn our backs and dig our heels in? As soon as the NB Government announced its new rules yesterday, various groups in opposition to shale gas development were quick to point out that these rules didn’t solve anything (or words to that effect) and that “gas still emits CO2”. Excuse me? Everyone knows that the world will not be converted to a carbon-free economy overnight, that we need at least 50 years to make significant progress and that – meanwhile – natural gas is the preferred fuel, the so-called “bridging fuel”. It is essential that we develop natural gas at the expense of all other fossil fuels.


This figure (click on it to enlarge it) shows household energy use in Canada as calculated by Statistics Canada for 2007, the most recent year for which data were available. The figures are a little confusing because of the way Statistics Canada calculates the percentages in each jurisdiction, but this graph is what I think represents their data best

The red bar represents natural gas usage. The overall Canadian figure is the one furthest to the left, all jurisdictions are plotted in geographic order, from West to East. The image leaves no doubt: the left side of the graph has a lot of red and there is virtually no natural gas usage east of Ontario. Out here in Nova Scotia, our household energy is supplied mostly by oil (imported mostly from the North Sea) and by electricity (which is produced largely by coal-fired power plants and that coal is imported from Colombia and Venezuela, and I honestly have no idea how environmentally friendly or humane those mining operations are but I’m not hopeful). Both oil and electricity therefore have had to travel thousands of kilometers before usefully feeding our energy needs. We also burn wood, more than any other jurisdiction. I want to address wood fuel in a different post some day. We may not have a lot of people here, but we have an unbelievably irresponsible energy usage for this day and age.

Nova Scotia has some shale gas, New Brunswick has a lot more. The reason for the difference is geological – their Carboniferous basins are a lot thicker than ours. The household energy usage of New Brunswick is comparable to that of Nova Scotia – no gas usage of any significance.

Developing unconventional gas is necessary in order to reduce emissions, regain control of our own energy usage and prevent the severe bleeding of workers to the West of the country.

The Maritime Noon website sports an ad for a Chevrolet Silverado, a car with an average gas mileage that is at best 30% higher than that of a sensible compact…………

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What is a natural disaster?

I recently watched a very informative webinar by Munich Re. It was their annual webinar on the world’s natural disasters, for 2012 that is. All Munich Re’s webinars are here. I highly recommend dedicating an hour of your time to watch some of these.

Munich Re is the world’s largest re-insurance company, i.e. it’s an insurance company for insurance companies. Because of the nature of that business, Munich Re needs to pay particular attention to natural hazards, since they generate the largest expenditures for insurance companies.

Munich Re distinguishes between the following types of natural hazards:

  1. geophysical hazards: earthquakes, volcanic eruptions and the related tsunamis;
  2. meteorological hazards: storms
  3. hydrological hazards: floods and landslides (they use the term ‘mass movements’)
  4. climatologic hazards: extreme temperatures, drought, fires.

I don’t want to get into the details of semantics here and I don’t want to argue with Munich Re’s categories, even though many landslides are part of the geophysical category and most floods and landslides are the results of storms.

Munich Re maintains an enormous (they claim: the world’s largest) database on these events, going back to 1980. Their figures indicate that all but geophysical hazards are increasing in number. The speakers in the webinar aren’t saying it directly, but they are certainly implying that climate change is the root cause of this increase in globally recorded natural disasters. James Hansen (NASA Goddard Space Centre) has always hypothesized that climate change would go hand in hand with an increase in catastrophic weather events, and this hypothesis is now beginning to be supported with evidence. Canadian figures appear to support the trends reported by Munich Re: the Insurance Bureau of Canada, “which represents the majority of private property and casualty insurers in Canada, says claim payouts from severe weather have doubled every five to 10 years since the 1980s” (CBC article here).

But what exactly is a natural disaster?

As part an undergraduate sedimentology and stratigraphy class, I developed a lab exercise on natural events that shape the earth’s surface and that leave a record in the form of sediments. The objective was to help students gain insight in the frequency and duration of events and then to think about the potential resulting sedimentary rocks.

I asked the students to determine how often an event typically occurred and how long the event would last.

Here is my list of events

  1. Asteroid impact (on the scale of the K/T impact)
  2. Catchment capture
  3. Debris flow
  4. Delta lob switching
  5. Flood basalt eruption
  6. Glacial lake sedimentation
  7. Hurricane / major storm
  8. Pelagic sedimentation
  9. River flood
  10. Sea level fall
  11. Sea level rise
  12. spring/neap tidal sedimentation
  13. surf on a beach
  14. tsunami
  15. turbidity current on an active continental margin
  16. volcanic ash fall

There was always lots of discussion about this list because of the uncertainty of geographic scale. Were debris flow to be considered globally? Were we talking about the surf on one beach or on all beaches of the world? The idea was to limit yourself to thinking about these processes within a sedimentary basin (after all, it was a sedimentary geology class), although some processes clearly had to be considered on a global scale (sea level fall and rise, asteroid impacts).

Each event had to be given a frequency on a scale ranging from of hundreds of millions (108) of years to seconds (10-8 yrs). The recurrence, determined for a specific order of magnitude is the Y-axis of the graph. It’s easy to see that a logarithmic scale with only 16 intervals can be nicely plotted on a (virtual) letter-size piece of paper. In addition, each event had to be given a duration, using the same time scale notation. I then asked the students to rank the events from least frequent to most frequent. The duration would follow.

I gave the students the numbers for glacial lake sedimentation: it occurs once a year (during spring melt) and it lasts maybe a few months. That means that the recurrence is 1, (100) and its duration is 10-1, as a month is more or less 1/10th of a year. It is important to think about more or less, because when you play with orders of magnitude on a 10log basis, then it doesn’t matter if a process lasts for example 3 or 5 years: in both cases it lasts less than 10 years and longer than 1 year, i.e. between two successive intervals.

While there were always some interesting differences between what students came up with, they generally (5 classes, 2 different universities, a 6 year period) came up with a graph that looked more or less like this:

events 1


My result for recurrence and duration of natural events. 

On the far left of the diagram is an asteroid impact. A big impact, such as the one that intercepted with Earth at what we now call the end of the Cretaceous era (65.5 million years ago) only occurs every few hundred million years. You can argue about how long they last, but you end up with figures between seconds and weeks, but certainly not more than that. Such events do big damage and several of these have been tided to so-called ‘mass extinctions’. Example: the end of what we now call the Cretaceous era is defined by the demise of large reptiles (“dinosaurs”) to the advantage – subsequently – of mammals who took over some of the dinosaurs’ niches. Likely that asteroid impact (the Chixtulub) caused the mass-extinction (a lot of other species became extinct as well), although the outflow of the massive basalts of the Deccan traps (in India) more or less around the same time may also have had something to do with it (such basalt outflows pump nasty gases in the atmosphere). Because of all the spectacular research around the finding of the end-of-Cretaceous Chixtulub crater in the Yucatan, the public and many scientists from other disciplines became more aware of these types of events, and we now send probes into spaces looking out for them, a sort of space traffic warden (Douglas Adams, rest his soul, would have a ball at that idea).  There was a bit of interesting press about asteroid Apophis last week. Apophis came in our vicinity, but is not expected to be anywhere close prior to 2036 (maybe).

At the other extreme, to the far right, is ‘surf on a beach’. Within one sedimentary basin it can go on for tens of millions of years, but each crashing wave only lasts a few seconds. We don’t think twice about it. In combination with rising and falling sea level, beach surf may eventually yield extremely thick coastal sedimentary sequences in the rock record.

In between are a whole bunch of other events (or processes, if you wish).

Again, you can argue about some of the details, but about 150 students came up with more or less comparable graphs.

What does this graph tell us? Let’s try to group these events.

events 2

The events on the left have a recurrence that is far longer than any human life span, with a result that humans don’t really worry about them (Apophis mostly caused of a lot of light-hearted banter on Twitter). The events on the right are also not something anyone ever worries or even thinks about much because they simply don’t cause any damage or risk.

But the events in the middle are the ones that worry us. Floods, ash falls, tsunamis, hurricanes, debris flows, and – even if you didn’t think about them – turbidity currents, because they (triggered by earthquakes) may cause tsunamis. These events, in the middle of a spectrum of natural events (and this list is not complete, you can dream up a whole bunch more, but it doesn’t really change the picture), recur at intervals that make them part of oral history, they become part of the human lifespan. They typically occur at intervals of hundreds to a 1000 years and they generally don’t last long, from seconds to days. Terror, in other words, is what they represent.

So what are natural disasters? Natural disasters are normal events, normal from the perspective of our planet. These processes shape our planet and have shaped it for hundreds, even thousands of millions of years.

Even though they are normal, when and where they occur remains the subject of probability calculations. If you live on the shores of the Gulf of Mexico long enough, you will experience a hurricane (I lived there for 6 years and experienced three hurricanes, fortunately they were relatively mild ones). But you will probably never ever experience an earthquake and associated tsunami. So you buy insurance against hurricane damage, but not against earthquake damage.

What MunichRe is saying is that the recurrence interval of the events that already fall within the spectrum of what we call ‘natural hazards’ is increasing. So there is more risk. Prepare yourself: your insurance premiums will go up.

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Dear Mr. Carney

That must have been a lovely stay, a “short week” (I’m quoting the Globe and Mail) with your family near the small village of Cheverie on the shores of our beautiful Minas Basin. As a proud constituent of Mr. Brison, I know the location of his house well, as it is the site of his annual constituency BBQ, always a terrific party with great music on that magic spot, the big field on top of the cliff overlooking the basin.

You must have frequently walked down to the beach at the end of the road (maybe you even went for a swim during those 2 hours around high tide) and I hope you took a moment to ponder the unusual sight there of a small outcrop of brilliant white rock shown in this picture with the steeple of the Cheverie church above it: cheverie point at macumber looking from cheverie point

A little closer, it looks almost eerie: TSOP 07 Cheverie anhydrite

This is an outcrop of anhydrite, which is a form of gypsum, if you wish. The gypsum belongs to what geoscientists call the ‘Windsor Group’, an assemblage of limestone, gypsum and salt that crops out (geoscience term for: ‘visible to the human eye without digging or excavating’) in the area around Cheverie. I’m sure you saw these outcrops on your drive to your holiday location. Nova Scotia has a lot of gypsum, an indispensable building material. The gypsum mine between Scott Brison’s house in Cheverie and his constituency office in Wolfville ran for about 80 years until it closed recently, one of the many victims of the global recession. It’s hard to get that gypsum out, as it needs to be shipped out of a basin with the world’s highest tides, hence the time window for ships to come in, load and turn around, is very short. Ingenious process technology was invented to meet those conditions, some of which you can still see at the wharf in Hantsport, but that ingeniousness made the whole process quite expensive, explaining why it recently collapsed.

Gypsum precipitates when seawater evaporates in shallow seas in hot wet climates. The gypsum (or anhydrite, to be correct) near Cheverie precipitated in shallow seas more than 300 million years ago, when what is now Nova Scotia was located more or less at the equator. Yes, we moved up quite a bit! Oddly enough, just below that gypsum are rocks that are full of organic material, even coal. Coal is fossil plant material and becomes preserved in hot wet climates, a situation that is diametrically opposed to the one in which gypsum precipitates. There is not yet a good explanation for this sudden climatic about-face. During hot and wet conditions, wide rivers ran through a lush green landscape, in which thick peat bogs (our future coal) accumulated. It was very fertile ground, where the first amphibians set foot on land in search of abundant food. Right in front of Scott Brison’s house is a surface, representing a fossil river bank, full of indentations that mark the location of of fossil trees: cheverie point tree roots in horton 1  cheverie point tree roots in horton3

Amazing, isn’t it? There are lots more amazing rocks along that same shore. I’m sure you saw the red rocks as well. They are the deposits of wild rivers that ran through a near desert environment in the middle of a gigantic continent. They look rusty red and that’s exactly what explains their colour: rust. The iron in these sediments became oxidized due to exposure to air. There was no sea or ocean anywhere at that time. These rocks are more than 200 million years old and Nova Scotia was located at about 15 degrees North at the time, the same latitude as many of the world’s great deserts now. It was a bleak time in the history of the earth, because the planet had just experienced a massive extinction which did away with 95% of all life. You won’t find a lot of fossils in those rocks, but there is evidence of some of the first dinosaur-like creatures in them. Most of these have been found along the north shore of Minas Basin near Parrsboro (where the lampposts are decorated with dinosaur lights).

And every day when you woke up, you looked across this magnificent basin and saw that big Cape on the horizon. That’s Cape Blomidon, a named that was morphed from ‘Blow Me Down’ (there is a place on the West coast of Newfoundland that also has that name, by the way). You can’t see a lot of detail in Blomidon from Cheverie, but maybe you took a day trip around the basin and visited Blomidon Provincial Park or even hiked Cape Split. I insert a picture of Blomidon here (taken on a very cold overflight one winter to photograph the ice in the basin): 668-6844_IMG

There is solid looking rock on top of Blomidon, very different in colour and texture than the underlying red rocks. The solid looking rock on top of Cape Blomidon is basalt. Basalt is definitely not a sediment. Basalt is extruded from the earth’s interior during times of so-called continent break-up. Pretty much like what happens in East Africa today where the Great Rift Valley marks a tear in the continent. The basalts of Cape Blomidon are about 200 million years old and mark the time when the Atlantic Ocean began to form.

And in between all this is loose sediment that may still become rock some day in the geologic future: the tidal sediments of Minas Basin and its eastern extremity Cobequid Bay, exposed only for a few hours, as shown here: met voetjes. Did you go and watch the tidal bore somewhere? I’m sure you learned about the efforts at generating electric power from in-stream tidal turbines. It’s not going as fast as everyone had hoped, but that’s because nature continues to be a difficult one to work with. I do hope that we’ll manage to harness the tides one day, so that we can run on cleaner energy while maintaining good stewardship of our unique environment. We should be able to do better than previous generations, who logged the place bare and hid the nutrient-giving marshes around the basin behind dikes. They are now a cherished cultural phenomenon, those dikes, but they do wreak havoc with ecosystem balances.

Did you come across a wonderful book called “The last Billion Years” (http://www.nimbus.ca/Last-Billion-Years-The-P5316.aspx) in Scott’s library? It tells the story of the geologic history of the Maritimes for the general public. I don’t mean to be disrespectful, you are not an average member of the general public, but you may not have a geosciences background, so I do recommend it highly.

In closing, I hope that you will tell many of your important relations here in Canada and, starting later this year in the UK, about our wondrous, amazing, natural environment which supported our economy, but – in a modern world with different economic drivers – also caused our decline. Raw resources alone are not sufficient to build a long term stable economy, value-added products is what builds a better chance at longer term prosperity. In the near future, we can hopefully capitalize somewhat on our unique geoheritage through the development of geoparks, building on the fame of the Joggins Fossil Cliffs World Heritage Site (http://jogginsfossilcliffs.net/)

With best wishes for a bright future on the other side of that ocean of which you observed the very beginnings right here on your holiday,


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The tidal landscape banner photo: Minas Basin, Nova Scotia, Canada


UPDATED December 29, 2014

This was my blog’s banner photo until January 1, 2015. What are you looking at? In a world of Google Earth where everyone has a GPS in their cell phone, I should start with the coordinates. You are standing at 450 6’ N, 200 33’ W, and you are looking North.

Minas Basin with banner photo location

Minas Basin, Nova Scotia. The pink trapezoid indicates the view in the banner photo

You are on the south shore of Minas Basin, which is the eastern arm of the Bay of Fundy, and this place has the world’s highest recorded tides: the average tide range (difference between mean high tide and mean low tide) is about 12 m, but it can increase to as much as 16 m.

The basin is about 80 km wide in an E-W direction and about 30 km at its largest N-S extent. It has a semi-diurnal tide (2 highs and 2 lows for each lunar day) and all that water comes in through the narrow Minas Passage. Actual tide charts are at http://tides.mobilegeographics.com/calendar/month/3799.html .

Minas Basin is surrounded by cliffs. The cliffs are exposed almost exclusively in soft sedimentary rocks, with the exception of the top of the Cape in the distance, which is exposed in Basalt. The cliffs therefore erode rapidly and new exposures are constant.

So this place is pretty much heaven for a sedimentologist. Which is what I am. I first became truly hooked on (clastic!) sedimentology while doing fieldwork for my Master’s thesis research in the macrotidal estuaries of the southwestern Netherlands, where the tide ranges is “only” about 4.5 m tide range.

This banner photo is pretty much the view from our house, which incorporates my office. I can’t think of living in a more interesting place, given that the people here are also really terrific.

Earth scientists categorize tide ranges as micro-(<2m), meso- (2-4m), macro (4-6m) or  hypertidal (>6m). Minas Basin and only a handful of other estuaries in the world are a category of their own with their extreme tide ranges. The only estuary that bears any comparison to Minas Basin is Knik Arm in Alaska, which has a 10 m average tide range.  Like Nova Scotia, that area was heavily glaciated during the Pleistocene and the glaciers left thick packages of sediments (tills, eskers, drumlines etc.). Also, Knik Arm is routinely covered in winter ice.

Another area of hypertides is is Ungava Bay in northern Quebec, which might actually have a marginally higher tide range than Minas Basin (difficult to measure), but there are no glacial deposits around Ungava Bay, because the area was scraped clean by the ice caps, leaving only bare rock exposed (easy to see on Google Earth). Famous for its extreme tides and tidal bore is the Bristol Channel / Severn estuary, separating South Wales from Dorset and Cornwall. Southern Wales was under ice caps during the maximum Pleistocene ice extent, but the ice didn’t reach across the Bristol Channel. The Gulf stream keeps this part of the world ice free year-round, even though it is at about 52deg N.

The extreme tide range of Minas Basin means that there is virtually no shipping. Too dangerous, the currents are as fast as Usain Bolt when he runs the 100 m dash. There are a couple dozen commercial fishing boats in this basin. Until a few years ago, especially designed vessels transported gypsum out of the basin, but the recession ended the demand for gyprock and the mine is now closed. In summer, we kayak here, though. We use a 2.5 hour time window just before high tide. It makes for interesting adventures.

Few people live here, but the interventions over the centuries have been more significant than you might imagine. About which more some other time.

Posted in General geoscience, Minas Basin, Bay of Fundy, Nova Scotia | Tagged , , , , , , , , , , | 2 Comments

Rachel Carson – as relevant today as she was 50 years ago

There is a new biography of Rachel Carson, the author of “Silent Spring”, which was published 50 years ago this year. The biography is by William Souder and is entitled “On a Farther Shore: The Life and Legacy of Rachel Carson”.

Full disclosure: I didn’t read “Silent Spring”. Of course I have been aware of it for as long as I can remember. The book came out in the year I turned 10, but I grew up in the Netherlands and so it took until I was a student in the ’70s to become aware of it. And by that time the book was already iconic, legendary and its thesis generally unquestioned.

I didn’t read the biography either, but I just finished reading a review of it in the New York Review of Books (Tim Flannery, “A heroine in Defense of Nature”, http://www.nybooks.com). By the way, if you can read only one periodical, then read the NY Review of books, which is about much more than just book reviews.

The most shocking bit of information that I learned from this article is this: in the early 1950’s, Eastman Kodak (in Rochester, NY) discovered streaks on its unexposed X-ray film. It turned out that the cardboard packaging of the film was radioactive. Why? It was produced in Iowa and Indiana by paper mills that used water from mid-western rivers, which were under the influence of radio-active fallout from the Nevada test site……

I am a baby boomer. We were born and lived our early years on a planet that experienced frequent and constant above ground nuclear testing. What that did to our health, nobody knows, because you can’t separate that influence from the influence of other poisons that we were routinely exposed to, such as pesticides, the main subject of Rachel Carson’s “Silent Spring”. Incidentally, it was her publisher who came up with that harrowing title.

Rachel Carson was already a well-known and popular nature writer when she published “Silent Spring”, so there was immediately a lot of attention for her new book. President Kennedy referred to it in a press conference that Fall in answering a question about curtailing the use of pesticides. But the chemical industry went on full attack, calling her subversive, a communist sympathizer, anti-business, a health nut, a pacifist and, predictably, a spinster.

Fast forward to 2012. In terms of pesticide use, the western world has accepted its detrimental effects. Environmental protection measures have improved matters significantly, although it could have been better. But society still struggles with (big) industry’s strong-arm tactics, and certain earth resources industries are not exempt from that behaviour either. Will they be proud of their present-day attitudes 50 years from now?

Rachel Carson felt that she had no choice but to write Silent Spring, quoting Abraham Lincoln: “to sin by silence when they should protest makes cowards of men”.

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A day to celebrate women in Science: Kiek Jelgersma

October 16 is Ada Lovelace day, a day to celebrate inspiring women in science.

What a great opportunity to write about two women geoscientists who I admired and knew.

First I will write about Dr. Saskia Jelgersma, better known as ‘Kiek’ (for Saskia). Kiek passed away in May of this year at age 82. There is an excellent obituary in English of her on the site of the Telegraph: http://www.telegraph.co.uk/news/obituaries/9317540/Saskia-Jelgersma.html. Do read it.

Kiek was a Quaternarist – she worked her entire career on the Quaternary, more specifically on the Holocene, the most recent 10,000 years of Earth history. Hers is the yet to be improved Holocene Sea Level curve of the Netherlands, the result of her PhD dissertation in 1961. To produce a scientific result that stands uncontested for this long is an astonishing accomplishment and points to her drive for perfection.

Kiek was fearless, loud, and – at times – abrasive. She was also loyal to the core, passionate about her science (and about anything else she happened to delve into). I met her a few times and became friendly with her (that wasn’t easy). I think she was the only working female geoscientist in the Netherlands for the first 15 years of her career. And there weren’t very many afterwards, certainly not until she retired (for a few years around 1990, I was one of them).

The Telegraph obituary mentions that she was awarded the ‘Van Waterschoot van der Gracht’ medal of the Royal Netherlands Geological and Mining Society (www.kngmg.nl) in 1997 at a special symposium (organized in her honour), entitled ‘Sea level and Science Fiction’. Yes! That’s true, I was president of KNGMG at the time and I organized that symposium and I had the privilege of presenting her with the medal. It was the first time I wrote a citation speech, and I discovered I loved doing that. Maybe this was the first and only time that Kiek was quiet, subdued, but only for a minute. When I finished reading the citation, she came up to the podium and whispered to me ‘this is a big moment for me, a big moment…’ (in Dutch ‘een groot moment’). To this day, she is the only woman ever awarded this medal, the highest honour of KNGMG.

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