Tom Thomson's Sunset Sky, Spring 1915

J.E.H. MacDonald and Lawren Harris met in the Studio Building in the spring of 1918. Tom's paintings from the Shack had been stacked in the Studio Building. Harris and MacDonald planned to sort through Tom's art, make comments on the back and distribute what they felt were the best examples of his genius.  "Sunset Sky, Spring 1915" was another of those panels and displays the distinctive "TT Estate Stamp". They were correct about the quality of the art but missed the real story behind this painting. They used a virtually identical name as they applied to "Sunset, Summer 1915". 

Recall that "Sunset, Summer 1915" was actually a sunrise painted in the spring of 1915 before the biting bugs emerged and a few days after the  May 22nd, 1915 volcanic eruption of Lassen Peak in northern California. That Creative Scene Investigation required significant effort but the facts were clear. MacDonald and Harris faced an incredible challenge to locate, time and identify the motivation of these paintings without any guidance from Thomson. My efforts in these blogs are simply to assist further as best as possible and to advance our appreciation of the art of Tom Thomson.  

Sunset Sky

Spring 1915

Oil on composite wood-pulp board

8 1/2 x 10 1/2 in. (21.6 x 26.7 cm)

Tom's Paint Box size.

Finding the location of this painting benefited from Tom not travelling far from Mowat Lodge in the spring of 1915. Tom was very faithful to the cloud structure and the terrain he saw - including individual trees. The following graphic will explain.

The terrain recorded in two other Thomson paintings from the spring of 1915 revealed several distinctive similarities with the skyline of  "Sunset Sky, Spring 1915". Hills and even groups of trees poking into the sky were repeated in the three paintings. Brushstrokes were also similar as Tom tried to represent the lay of the land - the ridges and hills. Subtle colour variations also depicted specific hills. The obvious conclusion was that Thomson was looking in the same direction across the northern basin of Canoe Lake in each of the above paintings. The eastern shore of Canoe Lake was back-lit at sunrise and the title of this painting as "Sunset Sky, Spring 1915" should have been "Sunrise Sky, Spring 1915".

The details of Tom's painting location from just in front of Mowat Lodge are also included below using topographical maps. The terrain of "Sunset Sky, Spring 1915" is compared with "Sunset, Summer 1915" with specific hills and ridges identified both in the paintings and in the terrain maps. 

The following comparative graphics will save many words. J.E.H. MacDonald and Lawren Harris reacted as most people would to the orange and red colours in the clouds and dubbed these works as obvious "sunset" paintings in the spring of 1918. 

The conclusion that can be made after comparing the colours in the sky is that "Sunset Summer 1915" (small inset image) was observed after May 24th, 1915. "Sunset  Sky, Spring 1915" was painted before May 24th and before the full impacts of the sulphate aerosols had reached Canoe Lake. The sunrise sky was still blue. A likely estimate would have Tom observing that sunrise on the morning of Sunday, May 23rd, 1915 but it is impossible, to know for certain. 

Now let's take a look at the weather situation that Tom observed.

The Conveyor Belt Conceptual Model is a great starting point
to better understand the weather - but remember that every 
system is different - otherwise, the forecast would be easy.
I based my imagined forecast for Sunday, May 23rd, 1915
(below) on Mowat Lodge being under the cyclonic
companion of the dry conveyor belt in the wake of the 
cold front - and the  rapid, anticipated approach of the
next warm conveyor belt which Tom might have recorded
in  "Sunset 1915". 

The meteorological clues that Tom painted above are all that we have. The gravity waves were extensive and regular and perpendicular to the westerly wind blowing at cloud level. The westerly winds would be consistent with the passage of a cold front. Those winds bringing cooler air had not yet broken through the stable inversion over the cold waters of Canoe Lake - the water was calm with no wave action. The gravity wave clouds would be riding the cold frontal surface as included in the following graphic. The more stratiform cloud on the eastern horizon would be the trailing flank of the warm conveyor belt. The patch of blue sky would be the dry slot of the jet stream that was driving the entire weather pattern. The weather pieces all fit together. 

I could be certain about the weather if I had been standing at Tom's shoulder and watching the clouds drift over the course of a few moments. Here is the weather forecast that I imagined  would follow that sunrise:

The winds would increase from the northwest by mid-morning. The overhead altocumulus would become increasingly patchy and dissipate as the cold front moved further to the east. Streets of turbulent stratocumulus would develop parallel to those winds as the sun continued to rise. The temperature would be slow to climb under the cold air advection behind the front as any heating from the sun must compete with the arrival of cooler air. 

Waves would develop rapidly over the lake and build over the fetch of Canoe Lake by the time they reached the eastern shore. The waves on the Mowat Lodge shore in the lee of the land would be minimal.  

By afternoon the streets of stratocumulus would have spread further apart allowing more sun to reach the ground. It would be a pleasant, bug-free afternoon. The northwest breeze would gradually diminish as the sun lowered on the western horizon. The skies would clear of convective clouds as the sun disappeared below the western horizon and the weather system exited far to the east. 

Any cirrus on the western horizon during the Sunday sunset would herald the next system that Tom would observe at sunrise on Monday, May 24th. The cloud and sky colours were becoming dramatically more vivid (and no one would know why). I wonder if Tom recorded that particular sunset - see Tom Thomson's "Sunset" 1915). An image from the Creative Scene Investigation of that particular painting is also included below.  "Sunset" 1915"  was painted from his favourite campsite on Hayhurst Point. The atmospheric ocean west of Canoe Lake should have been jammed-pack full of volcanic aerosols from Lassen Peak on the evening of Sunday, May 23rd, 1915!

If so, Tom would have paddled the short distance to his campsite on Hayhurst Point with a light tailwind in order to capture the colourful sunset and the startling arrival of the sulphate aerosols from Lassen Peak. The radiational inversion would set up quickly under clear skies. Canoe Lake would have become calm and an effective mirror for the volcanic sunset colours. Tom might have paddled back to Mowat Lodge at twilight or spent the night at his camp. 

My imagined weather forecast and sequence of events is based solely on  "Sunset Sky, Spring 1915", Lassen Peak and the typical progression of mid-latitude weather systems. As you might guess, I have a vivid imagination...

In any event, Sunday supper on the Queen Victoria Holiday weekend would have been memorable - not only because of the "fireworks" in the sky. Annie Fraser, Shannon's wife was well known for her fine meals and baking at Mowat Lodge. (Note: May 24, Queen Victoria's birthday, was declared a holiday by the Legislature of the Province of Canada in 1845. After Confederation, Queen Victoria's birthday was celebrated every year on May 24 unless that date was a Sunday, in which case a proclamation was issued providing for the celebration on May 25.) The Great War was still raging in Europe and patriotic feelings would have been high. 

The following graphic explains the potential correlations between three Canoe Lake sky paintings from the spring of 1915. I believe that Thomson accurately captured the approach of the volcanic aerosols from the eruption of Lassen Peak in California which exploded on Saturday, May 22nd. He also chronicled the coming and going of two consecutive mid-latitude synoptic-scale weather systems.  

• Number 1 on left "Sunset Sky, Summer 1915";
• Number 2 in the centre, this post "Sunset Sky, Spring 1915"; 
• Number 3 on right "Sunset, Summer 1915".

Tom did not leave any hints that might confirm that this Creative Scene Investigation (CSI) is correct. The interpretation hinges on the fact that Tom painted pretty much exactly what he witnessed. The science pieces all fit together quite beautifully but of course, we can never quite be certain if this is the truth. Regardless, CSI permits us to view Tom's art and science as though we were gazing over his shoulder and appreciating the beauty and inspiration of nature. 

As alluded to above, there could be four sequential paintings recording every sunrise and sunset at Canoe Lake starting on the evening of Saturday, May 22nd, 1915 - the day that the Lassen Peak volcano erupted. I hesitated as I feared that I was exceeding the limits of my credibility in weather prediction even though the events occurred more than a century ago. The potential paintings are included in order with a brief explanation in the following graphic. Please ignore the official names of the artwork which identify them all as sunsets - two of the four were sunrises as already demonstrated. 

Tom might have been aware that something very unusual was happening in the atmosphere. This lends some rationale for Tom to diligently observe the increasingly spectacular colours in a series of paintings. Paintings number 1 and 3 in the above series are the only actual sunsets. Painting 3 does fit the progression of the weather although the image is darker and the clouds more red, making it stand out. Its inclusion in the series is very plausible though as the first surge of volcanic aerosols would have just been arriving from California. The sunset colours would have been especially vivid with the western horizon loaded with fresh volcanic debris! The initial concentrations of aerosols can be very high behind the deformation zone of the airflow delivering those particulates. Tom Thomson's "Sunset" 1915 was likely painted at sunset on Sunday, May 23rd from Hayhurst Point.

Dispersion of the volcanic aerosols over the following months would eventually dial down the chroma of the sunrise and sunset skies to something approaching what Tom painted in sunset number 1 in the graphic. 

Inscription verso: 

• c., estate stamp; 
• u.l., in graphite, no filter
• National Gallery of Canada, Ottawa (1542)

Provenance;

• Estate of the artist
• National Gallery of Canada, Ottawa (1542). Purchased 1918

To really appreciate Tom Thomson, it is important to place his art within the context of the times in addition to the science and the weather. "Tom Thomson's Last Spring" does an admirable job of re-creating the era and the impacts of the Great War while incorporating as many historical facts as possible within his story. However, I will try to stick to just the science and the weather. 

Warmest regards and keep your paddle in the water,

Phil Chadwick

PS: Tom Thomson Was A Weatherman - Summary As of Now contains all of the entries to date. 

PSS: Should you wish to have Creative Scene Investigation applied to one of Thomson's works that I have not yet included in this Blog, please let me know. It may already be completed but not yet posted. In any event, I will move your request to the top of the list. If you made it this far, thanks for reading! 

PSS: If one searches Tom Thomson

Catalogue Raisonné for "sunrise" only one painting shows up. If one searches for "sunset" 25 works are produced. Some of those sunsets are actually sunrises as we have demonstrated. It would have been helpful if Tom had left a few hints. 

Tom Thomson's Sunset Sky, Summer 1915

One of the unspoken motivations for investigating the art of Tom Thomson is to encourage others to view nature and the weather as he did. A greater understanding of both leads to appreciation and perhaps respect. Conservation of the environment must certainly follow a thoughtful appreciation of nature. 

There are several very interesting aspects of meteorology that Tom included on this plein air panel. That is my motivation to include this work in the book although it was never included in the "Tom Thomson Was A Weatherman" presentation. That presentation would get much too long if everything was mentioned so only the essential and exciting weather works were ever included. I sometimes described this meteorology to my coworkers in the weather centre. Often though, the workload and deadlines would come rushing at us and the subtleties of the patterns in the sky and in the satellite imagery would have to be brushed aside. But not today... in addition, this research allows us to estimate when this painting was completed and it was not summer as suggested. 

Sunset Sky Summer 1915
Oil on composite wood-pulp board 8 1/2 x 10 7/16 in.
(21.6 x 26.5 cm)
Tom's Paint Box Size

Tom would have needed a stable platform to paint from in order to capture the details in the cloud structure. The obvious choice would have been his favourite camp on Hayhurst Point looking toward the western shore of Canoe Lake. The lack of distinctive terrain features is in itself an important clue. I have paddled there and was surprised by the simplicity of that western shore. 

 If one looks closely at Tom's painting, a distant forested hill can be seen on the lower right horizon. A back-lit forested ridge also slopes downward to the right. The rocky shoreline of the lake was in the foreground. Of course, there are many such vistas but the shore of Canoe Lake south of Mowat Lodge fits the constraints closely enough as depicted in the following graphic. 

This is certainly a sunset scene looking west because of the weather clues which I will describe. The cloud features establish that the winds were blowing left to right. The overcast clouds on the horizon were characteristic of a mid-latitude weather system and a warm conveyor belt of approaching weather. The source of heat and moisture rising along those isentropic surfaces in the atmospheric ocean was certainly to the south. Tom had to be looking west and the backlit scene required the timing to be a sunset. 

Langmuir Streaks are multiple cloud streets paralleling the wind direction. They occur in a marginally unstable air mass where helical circulations driven by the wind interact to form repetitive, linear cloud patterns. The spacing between Langmuir Streaks is related to the depth and degree of the instability. Langmuir Streaks are described in "Langmuir Streaks – Take the time to Observe and Learn from Nature" and in "Weather Watching Guide for Everyone…" - plus lots of other places in my blogs. 

The rotation evident in the cloud structures is especially interesting and deserves a more thorough explanation. This science is also described in several of my blogs including the following: "A Closer Look at Rotational Clouds", "Cloud Shapes from Rotation" and "The Theory of Unified Swirls".

I never go anywhere without my Coriolis arm and hand. If there is a secret to really understanding cloud shapes, it can be found in using your Coriolis body parts. Remember that the shapes of clouds are sculpted by the relative flows within the atmospheric frame of reference. Your right arm contains all of the tools you will need if you are in the northern hemisphere. Below the equator, your left arm contains the Coriolis insights into the weather. 

Mares tail cirrus (cirrus uncinus) is an excellent example of how to use your Coriolis arm, hand and fingers. Align your Coriolis arm (as in the above graphic) in the direction of the wind at cloud level. The guiding flow can also be determined by watching the cloud drift over the course of a few minutes. Unfortunately, the cloud drift option is not available in a painting or a photograph. Curl your Coriolis fingers in the same direction that the clouds swirl. If your Coriolis thumb points down, you are viewing an anticyclonic rotation. If your thumb points upward, a cyclonic rotation is revealed. The differential advection of these rotations with height results in the airmass either ascending or descending - typically in the direction your Coriolis thumb must point. The amount of cloud should also correlate with whether the air is rising or sinking. The tendency of the surface pressure is also directly correlated with how the air is moving vertically but most people do not carry a pocket barometer. 

The above graphic places Tom within the weather pattern revealed by the cloud. All of the puzzle pieces fit perfectly together. Tom was looking west-southwest in the spring of 1915 before the biting bugs emerged and fishing became his most important interest. The layers of cloud of the warm conveyor belt were rising along their northward journey on the isentropic surfaces. The anticyclonic swirl of the anticyclonic companion of the warm conveyor belt was overhead. The cloud-filled cyclonic companion of the warm conveyor belt occupied the western horizon. 

Combining these facts that Tom recorded in oils almost allows us to be standing with him overlooking his shoulder as he painted. The sunset sky is always beautiful. Notice however that the hues do not even come close to the sunrise colours of the also misnamed "Sunset, Summer, 1915" described previously here. That obvious lack of colour in a sunset sky was the essential clue in revealing this as a spring and not a summer 1915 painting. You might have noticed how I glossed over that statement above!

Lassen Peak erupted in northern California on May 22nd, 1915. Allowing for a couple of days to spread the sulphate aerosols to eastern North America, this subdued sunset painting had to be completed before May 24th, 1915! This sunset sky was observed in the spring of 1915 and not the summer as suggested. Sunsets are typically much more colourful than sunrises after a day of wind stirs dust into the lower levels of the atmosphere. However, this sunset does not hold a candle to the sunrise painted below after the volcanic eruption of Lassen Peak.  

Tom Thomson's Sunset Sky, Summer 1915 as
it would have appeared in his paint box.

Inscription recto: 

• l.r., estate stamp Inscription verso: 
• c., estate stamp; in graphite, 
• u.l., in graphite, 146 (or 47)? Mrs. Harkness; 
• u.l. corner, 15 (circled) Tom Thomson Art Gallery, Owen Sound (967.060) 

Provenance:

• Estate of the artist 
• Louise Thomson (Mrs. J.G.) Henry, Guernsey and Saskatoon, Saskatchewan 
• Tom Thomson Art Gallery, Owen Sound (967.060). 
• Gift of Louise Thomson (Mrs. J.G.) Henry, Saskatoon 1967

This painting bears the "TT-1917" estate stamp so it was among those that J.E.H. MacDonald and Lawren Harris assembled in the Studio Building during the spring of 1918. Tom's father John ensured that each of Tom's siblings received ten works so he probably played a role in getting this particular painting to Tom's older sister Louise (1873-1971) as part of her share. A March 11, 1931 letter from Louise to Blodwen Davies is well worth reading and puts the story of Tom Thomson into the more human and personal perspective that it deserves. 

Louise gave this painting among others to the Tom Thomson Art Gallery, The Tom which in her day was the Art Gallery of Owen Sound. An article in the Owen Sound Sun Times from October 23rd, 1967 tells the story: "Valuable Tom Thomson Works are Presented to Gallery by His Sister." I have presented "Tom Thomson Was A Weatherman" a couple of times at "The Tom" and always stop in to see my friends whenever I happen to be in Owen Sound.  

Warmest regards and keep your paddle in the water,

Phil Chadwick

PS: Tom Thomson Was A Weatherman - Summary As of Now contains all of the entries to date. 

PSS: Should you wish to have Creative Scene Investigation applied to one of Thomson's works that I have not yet included in this Blog, please let me know. It may already be completed but not yet posted. In any event, I will move your request to the top of the list. If you made it this far, thanks for reading! 

Tom Thomson's Burnt Area with Ragged Rocks, Spring 1915

This is another one of those sketches jam-packed with science. Creative Scene Investigation will peel back the layers of careful observation allowing us to better see the real motivation of Thomson. Tom was inspired by and immersed in the beauty of nature. Some of the clues are very subtle so I never included this painting in "Tom Thomson Was A Weatherman" presentations. Instead, I concentrated on the exciting thunderstorms and tornado panels. Otherwise, that presentation could last for days...

Burnt Area with Ragged Rocks
Alternate title: Northern River Spring 1915
Oil on panel 8 1/2 x 10 1/2 in. (21.6 x 26.7 cm)
Tom's Paint Box Size

Location is always the best place to start. We are fortunate that Tom had his favourite places to paint and I suspect that Tom sketched from almost this same spot a year later. The following graphics and terrain maps will explain - and save a lot of words. Tom was looking northerly across the Grand Trunk Railway tracks just east of the road between Mowat Lodge and Canoe Lake Station. Potter Creek was still covered in ice limiting access to more distant locations. 

Important CSI clues can also be discovered in the clouds and the illumination of the scene. The light was on Tom's back and left shoulder. Tom was looking northerly across the hilly terrain at sunset. A light southeast breeze was likely.  

The grey colour of the cumulus is another important clue. Cloud droplets grow with time. Water vapour condenses on the original droplets or atmospheric particles might simply adhere to them. This is especially true for clouds within the planetary boundary layer which are continually interacting with the earth. 

Larger particles scatter light more effectively in a forward direction - Mie scattering of energy. Front-lit clouds get darker with age as the larger scatterers send incident light energy forward and away from the observer of the front-lit scene. This implies that these cumuli generated by daytime heating had been around for a while - all day in fact and they appear quite grey.  New cumulus clouds generated by the first rays of the sun heating the ground in the morning are bright and white in comparison. 

The following graphic places Thomson within the weather scene and the sunset light on that early spring evening. A weather system was approaching from the west. Tom was within the storm's anticyclonic companion of the warm conveyor belt with less cloud overhead and the southeast breeze at the surface. The altostratus cloud he painted was rising in the frontal lift of the warm front. Typically there is less cloud south of the surface warm front. The sun still illuminated the scene as the cloud ahead of the cold front had yet to arrive. 

The bands highlighted within the altostratus clouds were another clue to discovering the CSI solution. The banding as painted by Thomson was regular and intentional in its depiction. Simply, there were swells in the atmospheric ocean. (see  "Wind Waves and Swells and Lines in the Sky" and "Keep an Open Mind" for more detailed explanations.) 

Thinner layers of altostratus moisture in the anticyclonic companion of the warm conveyor belt are very conducive to revealing the cloudy wave crests and cloud-free troughs. Swells are much more challenging to see in the cloudier cyclonic companion. (see "Tom Thomson's Islands Canoe Lake, 1916" for a specific example among many others.)

The absence of secondary wind waves suggests that the wind was also perpendicular to the swells as in the swell generation zone. As labelled in the following graphic, the cirrus level deformation zone was well to the north consistent with the altostratus cloud type. 

These features are evident in "Burnt Area with Ragged Rocks" if one just takes the time to examine the brush strokes carefully. All of the puzzle pieces fit together. Nature follows the laws of physics and Thomson was faithful to what he saw and inspired him. 

Tom’s time spent learning in the woods around Leith as a child opened his mind to the wonders of nature and laid the foundation for the art that would follow. Having an inquiring and open mind is a gift. If you paint what you see you do not need to understand the science… you just need to appreciate the natural beauty. Tom was a keen and accurate observer of nature. I am just trying to help.

Tom Thomson handling the team of horses
while Shannon Fraser in the lower right
looks on. Happy tourists enjoying the 
wagon ride to Canoe Lake Station. 

This is potentially another of those paintings where Thomson shared a wagon ride with Shannon Fraser during one of the trips to Canoe Lake Station looking for Mowat Lodge guests. The snow and ice made travel in the bush and on the waterways very challenging.  Thomson arrived in Algonquin Park in mid-March 1915. Tom travelled by train via Huntsville where he stayed at the home of Winifred Trainor for two days. 

Inscription recto: 

• l.r., T.T. (incised)
• Thomson Collection @ Art Gallery of Ontario

Provenance:

• Estate of the artist
• Laing Galleries, 1945
• H.S. Southam, Ottawa
• G. Hamilton Southam, France and Portland, Ontario
• Sotheby's Toronto, 20 November 2006, lot 57
• Loch Gallery,Winnipeg
• Private collection, Toronto
• Thomson Collection @ Art Gallery of Ontario

I happened to see the original painting at the AGO and remarked about the science in the sky that Tom had included to a few gallery goers assembled there. Every cloud has a story to tell. 

Warmest regards and keep your paddle in the water,

Phil Chadwick

PS: Tom Thomson Was A Weatherman - Summary As of Now contains all of the entries to date. 

PSS: Should you wish to have Creative Scene Investigation applied to one of Thomson's works that I have not yet included in this Blog, please let me know. It may already be completed but not yet posted. In any event, I will move your request to the top of the list. If you made it this far, thanks for reading!