Yesterday, I flew home to Toronto from the Netherlands, after handing in my PhD thesis. The plane had a camera pointing straight down that you could watch via the screens mounted in each seat. We had clear skies coming in over Labrador, and I spent the next two hours staring at the ground ten kilometers below. I normally take a window seat when I fly back, but this time felt like a new way of seeing Canada, a sort of involuntary real-time scroll through Google Earth. These words jumped out at me like popcorn and I thought I would share them.
What if it got so cold That it snowed every day For a thousand years?
So much snow That it piled up in drifts Three kilometers high
And flowed out Like pancake batter Across a precambrian griddle
Milling old mountaintops Into flour Our collective geologic trauma
Ten million fjords All pointing Into the sunset
Through Caravaggio clouds Unfurling roses Obscuring violence
Scars revealed By reservoirs Cursed news from another star
Windblown white floes Serrate inky lakes Like polished granite
Black spruce Persisting through Their boreal blankets
Leopard stripes And zebra spots On a gneiss throw rug
But then a road Too straight for this fractal tapestry Points home
Here are some photos; the resolution and clarity obviously don’t do the view justice, so the poem is my humble attempt to capture some of what I saw.
A few weeks ago, I was reading a book about glaciology recently when a sentence caught my eye. Many advances in our understanding of how glaciers developed and transformed our world during the last ice age came from studying the Canadian landscape. In particular:
A benchmark example [of paleo ice sheet reconstruction] was the compilation of the first Glacial Map of Canada in 1959, followed by its update in 1968, by the Geological Survey of Canada, based on painstaking aerial photograph and field mapping by its officers on a map sheet by map sheet basis after the completion of the aerial photograph coverage for the whole country in the 1950s.
This caught my eye, because I knew that my Grandpa on my Dad’s side of the family was a pilot who flew a lot of aerial surveys for the Canadian government in the late 50s. I mentioned this to my Dad, just thinking he’d say, “gee, that’s cool”, and move on. Apparently that triggered something in him though, because a few days later my email inbox was filled with a treasure trove of old family photos that I had never seen before. In recent years I have also developed an interest in Arctic coastal geomorphology, so this discovery scratched a couple of itches for me.
One of the photos was taken above Alexandra Fjord on Ellesmere Island, which is insanely far north (78°N!):
The cool thing is that when I went into Google Earth, I was able to snoop around and actually to find the same vantage point. To my surprise, it seems like the glaciers there haven’t changed much since my grandfather was there in 1957:
However, Dad pointed out that perhaps the glacier at the front hasn’t changed, but that the ice field behind it has shrunk. He probably has a point there…
Why was he actually up there, and what were they surveying? A series of radar transponders were set up across northern Canada so that the airplanes could precisely triangulate their positions . Based out of Ottawa, my Grandpa and his colleagues carried out many long flights between remote destinations A newspaper article from 1957 describes the tremendous undertaking that mapping the entire Canadian Arctic was, apparently the world’s most ambitious aerial survey operation at the time:
“SEVEN-YEAR JOB: Rockcliffe Squadron to Complete Mapping
Monday, March 25, 1957
“Planes from the RCAF’s 408 Photo Squadron at Rockcliffe Airport will fly to within 450 miles of the North Pole this Spring to complete the geodetic survey of Canada which it started seven years ago.”
“Using the huge USAF base at Thule, Greenland, and RCAF’s own base at Resolute Bay, both well within the Arctic Circle, the planes will criss-cross approximately 400,000 square miles of Arctic wasteland to produce reference points for the accurate mapping of Canada.”
“This year’s aerial mapping mileage will bring over 3,000,000 square miles – approximately 90 percent – of Canadian territory accurately surveyed by the Air Force. When the 300 men of the squadron return to base here about July 1, they will have completed the world’s greatest aerial survey operation.”
While the mapping operation may have been motivated by a Cold War-era push to map Canada’s north for defense purposes, the operation was also of great scientific benefit. In addition to providing a wealth of useful data for glaciologists, the measurements also provided important insights into other fundamental geophysical questions. For instance, the earth is not a sphere, but rather an oblate spheroid, or something like a squashed rugby ball. But even then, gravity is weird and complicated, so the rugby ball comparison only takes you so far, and precise measurements are necessary to figure out all of the actual irregularities in Earth’s shape.
Measurements like these have many applications, including for estimating sea level rise rates. By understanding how the Canadian Arctic is rebounding in response to deglaciation, scientists can better answer Tricky Questions About Sea Level Rise there.
One of my favourite stories from the 1957 article involved some of the corrections that were made to previous maps:
“Throughout the … programme, many positions believed to be accurate were found to be in error. In 1956, for example, Prince of Wales Island (in which the North Magnetic Pole was then located) was found to be three miles further south than was indicated on the map.”
“Although they didn’t possess any supernatural strength to move mountains, from such discoveries as this, the members of the 408 Photographic Squadron did, facetiously, claim the ability to move islands.”
I would thus like to think that all my researchon islands is simply carrying on a Pearson family tradition! My Dad (a civil engineer) also worked in the Arctic during the 1980s, constructing artificial islands in the Beaufort Sea. That’s a story for another time, though!
Speaking of Pearson family traditions, I can see that my Grandpa also had a clear eye for photographic composition, a gift that my Dad quite strongly inherited:
Another reasons I was so delighted by these photos is because one of my favourite painters, Lawren Harris, also spent a lot of time in the Canadian Arctic. I have always felt drawn to his dramatic mountain landscapes capped with snow, and nary a tree for thousands of miles. The mountains of the far north have a particular shape to them, which seems unique compared to most of the mountains I have seen with my own eyes.
I made it as far north as Lofoten in Norway (68°N), and have flown over parts of the Arctic on transatlantic summer flights, but have never actually set foot on those rugged and remote hills. Something for my bucket list!
Growing up in Canada, we were always taught that the Bay of Fundy, is home to the world’s highest tides. The difference between the highest high tides and lowest low tides is 17.0 m, plus or minus 0.2 m [Arbic et al., 2007]. When I was younger (long before I ever knew that coastal engineering was a career option), I had the good fortune of visiting the Bay several times, usually while en route to visiting my Mom’s family in eastern Canada.
When the tide retreats, tidal flats stretch for tens of kilometers, making you question which direction the ocean is actually in. The Hopewell Rocks (pictured above) are revealed, and tourists wander the base of beautiful red cliffs. Then right on schedule, the tide returns, and everything is bathed deep in chocolate milk for 6 hours.
However, 1600 km due north of Fundy lies Ungava Bay, which is also fighting for first place in the World’s Highest Tides Competition. Flanking Hudson Strait (which connects Hudson Bay to the Atlantic Ocean), Ungava Bay has a maximum tidal range of 16.8 m, plus or minus 0.2 m [Arbic et al., 2007]. This means that the difference between the Bay of Fundy and Ungava Bay is so small that it is within the limits of what we can measure- the jury is still out!
How do the tides grow so large in these bays? The answer is resonance. Tides generated by the gravitational pull of the moon rise and fall every 12.4 hours (one tidal period). By coincidence, the time it takes a tidal wave (i.e. one full cycle of low water to high water and back to low water) to travel the length of Ungava Bay is 12.7 hours [Arbic et al., 2007]. This means that a new tidal wave is coming into the bay just as the old one is coming out. If you push a child on a swing, they will travel much higher if you properly time your pushes with the rhythm of their swinging. The same holds true with tides moving in and out of a bay, and we call this phenomenon resonance.
The speed at which a tidal wave travels depends on the depth of the water, the shape and size of the bay or estuary it moves through, and friction from the seabed. The consequence of this is that changes like sea level rise and the construction of tidal power stations or storm surge barriers can actually modify the behaviour of the tides. For instance, an increase in sea level rise could bring Ungava Bay even closer to that 12.4 hour resonant period, and further increase the tidal range there [Arbic et al., 2007]. However, this would require 7 m of mean sea level rise to increase the tidal range by just 2%, which I think would be a much bigger problem…
Usually friction from the seabed is one of the main factors that affects tidal waves in estuaries, dissipating energy and damping out their range. However, a recent study by my TU Delft colleagues Kleptsova & Pietrzak  found that friction at the surface of the water from sea ice can also have a moderating effect on tidal amplitude. As a consequence, the tidal range in the far-north Ungava Bay actually decreases during the winter. This suggests to me that Fundy remains the World Champion at Christmas, but that during the summer, it’s still anybody’s guess.
An interesting question (and the one that sparked my curiosity to write this post in the first place) then becomes: how might our tides change in a world where the Arctic no longer fully freezes over? To me, this is just one more example of the scary Pandora’s Box that humanity has opened with rapid climate change. If something as seemingly dependable as the tides can change, what other surprises will nature have in store for us?
Last week, the Newfoundland (on the east coast of Canada) got hit by a record-breaking storm: a “hurricane blizzard”, with 150 km/h winds, >10 m waves, and almost a metre of snow. Newfoundlanders are no strangers to bad weather, but this is rough stuff even by their standards.
In a fit of procrastination, I started wandering around Newfoundland in Google Earth. The Strait of Belle Isle separates the northern tip of Newfoundland from the rest of Canada, and is often frozen over in the winter. When this ice breaks up in the spring, it makes beautiful patterns from space. What struck me was that the broken ice floes looked a lot like the microscopic sand photographs I have been posting on this website:
Apparently the shape and size of sea ice floes is largely governed by ice melting, collisions and mergers between floes, and breakup due to flexing by ocean swell waves (Toyota et al., 2006). Even though the specifics of the mechanisms moving and shaping sand grains on the seabed at millimetre scales are different from those acting on ice floes one million times larger, the same general laws of physics still apply. This is one of my favourite things about nature: there is great beauty in finding similar patterns at different scales in completely different contexts!