Exploring weather and all it entails

Welcome to the DRAW Blog! Our focus here is to introduce topics related to DRAW and weather. This could be background information about parts of the project, such as symbols, discussions on weather issues, such as climate change, or may simply be a way to get to know the DRAW team further. Check in every other week for new posts!

Horizontal and Vertical Montreal

by Victoria Slonosky       on July 17th 2019

This week on the DRAW blog : look at how the vertical and horizontal city can affect weather!

The urban heat island effect is one that’s well known to many city dwellers- the fact that heat tends to accumulate in large (and even not-so-large) built up areas, partly due to land use and partly due to heat sources from energy use by people. Roads, concrete, asphalt, buildings and other man-made structures all have different heat and water absorbing or shedding characteristics than do natural surfaces such as forests, grass and wetlands.

Large cities like Montreal have changed enormously in extent over time, starting from small centres, currently known as Old Montreal covering a few square kilometers in the early 19th century when continuous weather records began (Figure 1) to covering nearly two thousand square kilometers of urban conglomeration, suburbs and exurbs today (Figure 2).

 Island of Montreal

Figure 1: Annotated map of the Island of Montreal, 1834 (Original from Bibliothèque et Archives nationales du Québec

 Island of Montreal

Figure 2: Island of Montreal, 2013

But not only has the horizontal extent of downtown Montreal changed, the vertical profile has as well.

For much of the 19th century, the Montreal skyline was dominated by churches, and most especially by the towers of the Notre-Dame cathedral. The cathedral towers could be seen from miles away and feature prominently in every landscape depicting Montreal (Figures 3-6).

 On the Saint Lawrence River

Figure 3: Travelling in winter on the St-Lawrence river, 1866 (Library and Archives Canada, MIKAN 2897892)

 Montreal from Saint-Helen's Island

Figure 4: View of Montreal from St Helen’s Island c.1830 (Library and Archives Canada, MIKAN 2837606)

 Ice road from LaPrairie

Figure 5: Montreal from the Road to LaPrairie over the Rapids (Philip John Bainbrigge (attributed to) 1837, 19th century M968.97, McCord Museum)

 St. Lambert's Road

Figure 6: St. Lambert's Road, Montreal, QC, about 1870 (Alexander Henderson about 1870, 19th century MP-0000.1452.59, McCord Museum)

With the development of Montreal as a major port, and especially the construction of the huge grain elevators from the turn of the 20th century, and the proliferation of skyscrapers from the 1930s onwards,the vertical profile of the city of Montreal changed as well. The Sun Life building, completed in 1931, was the largest building in the British Empire at the time, with 24 storeys (though the Royal Bank of Canada building, near the cathedral on St Jacques / Saint James Street, was several storeys higher). Today, it’s almost impossible to find the towers of Notre-Dame amidst the soaring building surrounding the cathedral (Figure 7).

 Recent Montreal photo of the Cathedral

Figure 7: This more recent picture is taken from approximately the same vantage point as Figure 5 (Vicky Slonosky)

What does this mean for the weather? As downtown residents and workers can attest, the tall buildings often act as wind tunnels, funneling icy cold blasts down the artificial canyons from Mount Royal to the Saint Lawrence. The presence of tall buildings can also affect convection, changing vertical air movement and leading to more cumulus clouds and thunderstorms around urban areas. Increased warmth in winter, as well as active measures to melt snow and ice, contribute to the formation of slush, which then freezes into icy surfaces overnight. The inhabitants of a city truly can create their own climate.

In addition - if you are interested in having a great look at the vertical and horizontal changes yourself check out the lookout at the top of Mont Royal, La Grande Roue de Montréal in Old Port, or Musée Point à Callière where there is an exhibit on the changes!

Handwriting Help

by Rachel Black       on July 3rd 2019

Old handwriting can be difficult to read and interpret, even for the experienced. Are you having difficulty reading the pages you are transcribing? Look no further - today’s post is about tips and tricks to reading old handwriting.

I wasn’t aware of this before, but the study of old writing in fact has its own name : Palaeography! This discipline focuses on the reading, deciphering, dating and context of old documents throughout history. It is crucial for historians and philologists to be familiar with this discipline because language and the way we write is constantly evolving over time - to understand a document you are studying you need to know how it was created! This of course, is not to be confused with Graphology, which is the study or analysis of a person’s handwriting in order to identify personality, emotional state, or the person itself. Graphology is a little more controversial and seen as a pseudoscience in some circles.

It can be difficult to read old handwriting for several different reasons. Is it a diary, ledger, administrative record, or personal correspondence? Or none of the above? Each of these documents might have different short forms, abbreviations, or different handwriting which could cause the document to be difficult to read. Our own weather ledgers have predetermined short-hand which might not be known to the general layperson and which might not be found in personal diaries or correspondence of someone unconnected to the weather world.

Or spelling could be an issue. In older documents the letter ‘i’ could be substituted with a ‘y’ or the letter ‘s’ with a ‘f’. In addition, there are types of ‘mirror writing’ that can occur. I have personally seen this in notes my grandparents have made where they have inverted their ‘n’ to look like a ‘u’, their ‘w’ to look like a ‘m’ and vice versa! This can make for some amusing or confusing reading!

Or they could have used a technique such as cross-hatching (also known as cross letters or crossed writing) which was used to save paper and thus postage in the 19th century. By writing overtop of an existing part of the letter, in the same ink in one sitting, it can be difficult to distinguish specific letters or words without practice. This requires a little more patience to decipher and luckily it is not common practice in ledgers.

 Cross-hatched letter

Here is an example of a cross-hatched letter (Wikipedia Commons).

Overall, learning how to navigate older handwritten primary source documents is extremely beneficial and takes practice, so don’t get discouraged! Here are some helpful tips and tricks on how to deal with handwriting on our weather ledgers:

  1. If you find something you can’t read - don’t panic!

  2. Even the most experienced historians can have difficulty reading older documents. Take a deep breath, or a break, and carry on.

  3. Check the resources available

  4. Under Meteorological Observations there is a handy chart for symbols, including those which are single letters or combinations of letters - check here to get an idea of what might be the closest to what you are seeing on the page Or check out the drop down menus that are available in the Transcription Panel - these have little images showing the options that could present in these cases - like cloud types or wind directions!

     Transcription panel dropdown

    The drop down menu for Clouds in the transcription panel has images to help!

  5. Look for clues on the page - words/letters/numbers

  6. Is there anything else on the page that can help you identify it? Compare other letters or words or numbers to see if they are similar and hazard your best guess.

    Check your numbers against others on the page - is this 7 similar to that 7? Or is it actually a 1?
    Also, if you are looking at temperature, cross check it against the time of year! A temperature of 73F is not odd for the summer, but in the winter? Probably actually 13F!

     Example of number comparison

    Is this a 2? A 7? Checking other parts of the page can clear up this confusion.

  7. Spelling

  8. If it’s an issue of spelling getting you down, sound out the word. No spell-check can create some pretty interesting spellings so think phonetically!

  9. Ask for help

  10. Ask around! Ask your friends what they think; if you are at a DRAW event, ask those around you; Ask us via Facebook, Twitter or email what we think!

Or if you are truly stumped and no one else is sure, feel free to mark it as illegible! This will let us know that something wasn’t clear and we can get back to it for further review.

 Illegible option

Feel free to select illegible.

Check out these interesting reads on palaeography, graphology and other tips of the trade when reading old handwriting!

Wikipedia - Graphology
Wikipedia - Palaeography
Graphology Handwriting Analysis
WikiHow - How to Read Old Handwriting
Ancestry.com - Tips for Reading Old Handwriting
UK National Archives - Palaeography
Find My Past Blog - 11 Tips for Reading Old Handwriting
Wikipedia - Mirror Writing

Guest Post: Air Quality in Montreal

by Geoffrey Pearce       on June 19th 2019

Please join me in welcoming Geoffrey Pearce to the DRAW Blog!
Geoffrey Pearce has been teaching in the department of geography at Dawson College since 2011. Prior to that he completed a master's degree in planetary science at the University of Western Ontario with a research focus on the geology of the northern plains on Mars. His attention has since shifted to Earth and helping students to engage in urban field studies and citizen science projects. Today he will be talking about Air Quality in Montreal

 Ste. Catherine and St. Laurent Blvd, 1875

Figure 1: An engraving showing a shoe factory at the corner of Ste. Catherine and St. Laurent Blvd in 1875, with smoke being released from chimneys (source: Canadian Illustrated News, Dec. 1875/BANQ)

In the opening of his landmark 1897 study ‘The City Below the Hill’, the sociologist Herbert Ames draws a contrast between living conditions in the well-to-do Montreal neighbourhood of Ville-Marie, ‘The city above the hill’, and living conditions in the poor and industrial areas along the Lachine Canal, ‘The city below the hill’:

“Looking down from the mountain top upon these two areas, the former is seen to contain many spires, but no tall chimneys, the latter is thickly sprinkled with such evidences of industry and the air hangs heavy with their smoke.”

Ames’s text provides detailed insight into economic and social conditions in neighbourhoods along the Lachine Canal, but there is only vague mention of the smoky air. A similar sense of ambiguity recently struck me when looking at the DRAW website and seeing the word ‘smoke’ written in the margins of a meteorological entry made on McGill campus in June of 1878. Was this smoke from a distant forest fire, or from people in the city burning coal and wood? Was it a localized phenomenon or did it span the city?

 Smoke in the Ledgers

Figure 2: remark about smoke from an entry at McGill's observatory on June 15, 1878, taken from DRAW website

This spring I put the challenge to students in an Environmental Studies course at Dawson College, where I teach geography, to describe how air quality in Montreal has changed since the late 19th century.

Students had trouble finding discussion of Montreal’s air quality in the late 19th and early 20th centuries, and connecting entries of ‘smoke’ from the DRAW page with other sources proved challenging. This is related to the nascent state of public health science at the time, but is probably also influenced by the fact that air quality was so persistently poor that heavy smog was not newsworthy. Wood and coal were the main sources for cooking and heating, and a variety of industries that have since disappeared from the city landscape added to the unhealthy atmospheric mix. At the end of the assignment, several students expressed gratitude that the city smells much better than before. I suppose that this is one way to appreciate our heritage!

Today, the Air Quality Health Index is displayed on screens while waiting for the metro, and chasing up data from specific monitoring stations is relatively simple. A quick Google search yields peer-reviewed studies about risk factors for particular boroughs, and controversies surrounding air quality - such as debate about the fate of wood burning ovens in pizzerias and bagel shops - are regularly covered in the news. The challenges that students encountered in describing the current state of air quality in the city were related to the abundance of data, rather than its paucity.

With the semester over and the assignments graded, I was left reflecting on how difficult it is to create a succinct answer about the how, where, and why of Montreal’s changing air quality. The shift from coal to hydroelectricity beginning in the mid 20th century reduced smoke substantially, but globalization and the local disappearance of many industries was also significant, as were emissions regulations shoehorned by property developers in the 1930s. Many students were surprised to learn that coal-fired power plants in Ontario made significant contributions to pollution in Montreal until they were phased out a few years ago. And these are only a few of the main variables. While neighbourhood differences in inequality and exposure to environmental hazards in 19th century Montreal are striking, some students compared this with the current contrast in air quality between uphill and affluent areas, such as Westmount, and lower income communities bordering industrial sites, such as Montréal Est.

 Smoke graph

Figure 3: the graph shows the # of smoke days recorded at Dorval Airport for each year between 1953 and 2018; the drop in smoke days was strongly influenced by the shift to hydroelectricity (graph courtesy of Victoria Slonosky)

The general trend for air quality in Montreal in recent decades is one of significant improvement, but I have found that students are much more aware of harmful but short-term events then they are long-term trends. One of the drivers of science is to understand and respond to things that were formerly invisible or misunderstood. In this sense, increased awareness and measurement of smoke, and concern about its health effects, can be seen as reflective of impressive and hard-won progress. We can look to the past to understand how progress occurred and to help guide us as new challenges occur.

Weather Symbols in Real Life

by Rachel Black       on June 5th 2019

Weather symbols are important to the transcribing of weather data as they explain without words weather phenomena that is being experienced. We have dedicated a section of our website to exploring the different weather symbols we use in our transcription interface (Meteorological Observations) and a couple months ago looked at the history of weather symbols on this very blog (International Communication: Weather Symbols). But do we really know what the symbols mean when they are defined as ‘hoar frost’ or a ‘solar corona’?

This series will explore real life images of the weather symbols - taken by our own team!

Lunar Halo

Captured by our developer, Rob

 Lunar halo symbol

 Lunar halo real life


Captured by team member Rachel

 rainbow symbol

 rainbow real life

Solar Halo

With two small “mock suns” or “sun dogs” on either side, captured by team lead Vicky

 solar halo symbol

 solar halo real life


Captured by team member Rachel

 overcast symbol

 example of Overcast sky


 Example of Clear sky


Show us your own examples of symbols in real life on Facebook or Twitter!

Who Were the Observers?

by Victoria Slonosky       on May 22nd 2019

This week we will explore a little about the individuals who were taking the observations we are transcribing.

The McGill observatory was originally founded by Dr. Charles Smallwood. An emigrant from England, Smallwood arrived in Montreal in the 1830s and set up a country practice in St Martin on the island north of the island of Montreal, then called Ile-Jesus, and now called Laval. By the 1840s, he had built an observatory with an impressive array of home-made instruments and arrangements for automatic recording. In 1863, he was invited to move the Observatory to McGill College. For some time it was known as the Montreal Observatory.

 Dr. Smallwood

Dr. Charles Smallwood

Smallwood had an honorary position as Professor of Meteorology, but he wasn’t paid to be a Professor or a weather observer, and although the observatory had some subsidy from the Meteorological Service of Canada (MSC) for instruments and for student assistants, he continued to earn his living as a doctor, living in Montreal on Beaver Hall Hill. One of his student assistants, Clement McLeod, was given permission by the College to room in the main building to make it easier for him to take observations in the adjacent Observatory.

 Clement 'Bunty' McLeod

Clement "Bunty" McLeod

Smallwood died in November 1873, without an obvious meteorological successor. After some consultation with the Director of the MSC, George Kingston, McLeod, who had just graduated in Civil Engineering, was nominated to take over the observations. MacLeod was dispatched to Kingston in Toronto with a number of the instruments for a crash training course, and observations resumed in January 1874.

McLeod was the Director of the Observatory for the next 40 years, until his death in 1917. Letters from 1875 show that salaries were paid for the Superintendent and two assistants. In 1880, McLeod applied to have a “the desirability and necessity” of residence built at the Observatory for the observer consider; this was granted and a house was built onto the Observatory building, where McLeod and his wife raised their family.

 McLeod with his students

McLeod with surveying students

We know one student assistant was James Weir. Another, A.J. Kelly, graduated in 1911, served in the Princess Patricia regiment in World War I, and returned to McGill, where he eventually became Superintendent of the Observatory in turn.

A budget for 1937-93 has listed the salaries of the Observer, A.J. Kelly, Weather Man, J.C. Kelly, and Day Clerk, C.L. Henry. Further wages are listed “for exposure of Sun Card”. A later document describes Charles Henry as having been the Chief Observer in 1958 “for over twenty years”.

If you'd like to learn more about the observers and the history of the observatory itself, don't hesitate to contact us!

Communicating Weather: Storm Warnings and Telegraphs

by Victoria Slonosky       on May 8th 2019

This week we will look at how weather, especially dangerous weather, was communicated in a time before telephones, cell phones and the internet. It is no surprise that weather observations played a significant part!

Space and Time: the Observatory, The Transit Telescope and Longitude

One of the most important functions of the McGill Observatory, and one which brought in much needed revenue to help pay for the meteorological and other scientific observations, was timekeeping. Timekeeping is fundamental to any kind of observing. In the 19th and early 20th century, timekeeping relied on observing the transit of certain stars. Midnight was defined as the moment certain stars, depending on the season, passed overhead. The transit telescope was one of the most important instruments in the observatory, although for timekeeping purposes it didn’t need to be as sophisticated and powerful as for astronomical discovery.

                      transit telescope

Accurate time was important in the age of railways to co-ordinate schedules, but was also crucial in determining longitude, both for ships in an Empire connected by sea and across the North American continent being surveyed, mapped and settled. Time and space are linked by the Earth’s rotation; the Earth rotates through 15 degrees of longitude every hour. With an accurate clock, the difference in time between two places can also be translated into the difference in longitude between those two places, and location can be determined. Somewhere 4 hours west of Montreal is also somewhere 60 degrees west of Montreal.

Clement McLeod, the Observatory’s second Director, used time and the exchange of telegraph signals with Waterford, Ireland in 1891 to obtain the most precise determination of longitude in North America for the McGill Observatory. McGill’s time signal was communicated to Montreal’s harbour, then one of the busiest in Canada, and by telegraph to Ottawa and westwards across the country. Once telegraph lines were laid under the Pacific, the time signal travelled across the ocean as far as Australia.

Storm warnings and telegraphs

Time was also very important for weather observations, both for exchanging weather observations across many time zones and for tracking fast moving weather like storms. Before the telegraph, storms moved faster than any human communications could. If a storm developed on the Great Lakes and passed up the St Lawrence towards the Atlantic, it moved faster than a rider on a horse or a ship could travel to warn people downstream in the path of the storm that danger was on the way- to say nothing of the hazard of trying to travel in a storm. With the invention and widespread use of the telegraph in the second half of the 19th century, for the first time there was a means of communication which could travel faster than weather systems, and so storm warnings became possible. It was to develop storm warnings, and to try to lessen to terrible losses of life from shipping at sea, on the St Lawrence and on the Great Lakes that the Meteorological Service of Canada (MSC) was first started. For many years, the MSC was a part of the Department of the Marine.

This is the reason the observations times in the McGill records tend to be at odd, but precise times such as 7:48 am or 11:13 pm. It’s partly to allow for synchronous observations across many longitudes, and partly to allow for the weather observation collators at a central observatory such as Toronto or Washington enough time to receive all the reports by telegraph, plot them all on a map, analyze the results and then issue a storm warning or forecast at, say 9am or midnight.

We will see you next time with more information on the principal observers at the McGill Observatory!

Introducing DRAW Members: Vicky Slonosky

by Rachel Black       on April 24th 2019

This week we will explore who is behind our project, starting with Vicky Slonosky!



Vicky Slonosky


Montreal (south shore) via England, France and Toronto and back to Montreal

Role at DRAW:

General wrangler & worrier, and historical weather data expert

Favourite Part of DRAW?

The enthusiasm! Everyone working on it is there because they want to be, and because they believe it’s an interesting and worthwhile project.

Favourite Season? Why?

Autumn- after the summer heat, the relief of the first cool breeze and hint of chill is like a promise of renewal- I think we should start our new year in October. Also, harvest season is a great time for any baker.

Favourite Weather Symbol? Why?

Tough one to choose, but I think snow drift, because it’s so quintessentially Canadian, with “poudrerie”, “blowing” and “drift” seen in the earliest Canada records going back to the 18th century (though admittedly often accompanied by words such as “violent", “affreuse" and “horrible"!)



Favourite Cloud Type? Why?

Cumulus- I love watching them grow, change shape, and billow out against a bright blue sky. Also very cool when they become dark and turn into dramatic storm clouds.

                      Plate 3 from Luke Howard’s Essay on the Modification of Clouds (1865)

Coolest thing you've learned while participating in DRAW?

The sheer number of people who are interested in weather and giving up their precious free time to type in old weather records, as well as the variety of way people have found to use the results.

And of Course:

Sweet or Salty?

Sweet (I'm a baker)

Star Wars or Star Trek?

Star Trek. I used to do all my math homework watching after school reruns

Cats or Dogs?

Allergic to cats, so dogs, but would be happy to have cats if I could

Favourite Animal?

Chickadees. I watch them from my kitchen window and have a special bird feeder only they can get into

Favourite place in Montreal?

So many to choose from! Toss up between St Helen’s Island for outdoors and BAnQ for indoors.

If you'd like to find out more about Vicky Slonosky and her work with DRAW check out our News page or explore the following:

Keep checking out the blog to see more DRAW Member Introductions in the coming weeks alongside our usual content!

Marginalia in the Ledgers

by Rachel Black       on April 10th 2019

Welcome to the third installment of the DRAW Blog! This week we will be discussing Marginalia and the incidences of marginalia which we have found in our own ledgers.

Have you ever encountered a book in which someone wrote in the margins? Or did you ever draw or doodle in the margins of your class notes as a student or while in a meeting? If you have, you have either encountered or created marginalia.

Marginalia are marks that are made as additions to an existing book or document. Specifically marginalia can be drawings, scribbles, comments or critiques which appear in the margins (or sometimes between the lines of the actual text too!). These marks can be placed by a reader after the fact (like if you wrote in notes regarding the text content in order to help organize your thoughts) but can also be created by the author or publisher during the documents’ creation. This can be seen in many biblical manuscripts through liturgical notes in the margins and even in popular fiction, like in the case of 16-18th century copies of Reynard the Fox where moralistic notes are placed in the margins for readers to muse on.

A good example, and one of the better known ones is the marginalia found in medieval manuscripts. Scribes would test their pens on the outer leaves of the manuscripts, and later books, to ensure their strokes would be consistent. These marks could be as random as scribbles or be the full alphabet, musical notation, or drawings. In one case, even a cat added marginalia to the manuscript, leaving paw prints on the pages! You will also see instances of marginalia in archival documents, such as personal papers. McGill University Archives holds private fonds from individuals and some contain marginalia, like the Ross Family Fonds which contains doodles in the student notes of Dorothy Ross - she drew her professors during class!

But why does marginalia matter?

Marginalia can provide a different layer of understanding to the document for modern day readers as information about the construction of the document and who was doing the writing is not usually recorded. As a result, these random doodles can tell us about trends (styles of writing in different parts of Europe for example) or even about the people involved. Marginalia is incredibly important to historians and archivists - even Citizen Scientists too!

We were surprised and excited then that while digitizing the ledgers for transcription that we found marginalia in the pages. Highlighted today are 8 images from ledger pages dating from 1902,and 1904-1906. The marginalia found in our ledgers are interesting; they appear to be something possibly to pass the time as they are not notes or commentary or pen tests - they are specifically portraits of people



Our observers have drawn several people they likely knew in profile view, replicating not only several men (with impressive facial hair) but also several women with fancy up-dos and details such as dress ruffles and hair accessories.



We honestly don’t know too much about these doodles as of yet - a few of the men have names scrawled underneath them and one of the portraits is initialed. We will have to research further into who these people might be or who could have drawn the portraits - all which could provide context to the observatory at the time and who was involved!




If you are interested in reading more about marginalia check out the following:

Or, if you would like to see the marginalia featured here up close, contact the McGill University Archives here.

International Communication: Weather Symbols

by Victoria Slonosky       on March 27th 2019

Welcome to another DRAW Blog post! This week we will be looking at the why and how of weather symbols.

While transcribing you may have come across little symbols used to depict different types of weather, rather than writing. It was one of the most difficult challenges we faced in designing our interface in fact. We can’t just ask our citizen scientists to type them in - there are no keys for these symbols after all! Do we provide a table to consult? Do we ask them to type them in as “rain” or “snow”? What sort of standard should we use that is both accurate and easy for citizen scientists to transcribe?

Our developer Rob came up with the answer: a drop-down menu which let the users match the handwritten symbol on the page with a list of pre-determined symbols. We created this list from a variety of print sources, including the Instructions to Observers (1878) by George Kingston, the director of the Meteorological Service of Canada and Hints to Meteorological Observers (1908, 6th edition) by Marriott.

This difficulty we faced in trying to figure out a standard to transcribe the weather symbols is not new. The idea of trying to use standard words to describe weather goes back to at least the 18th century. One of the first attempts to coordinate standardized international weather observation was undertaken by the Societas Meteorologica Palatina, in Mannheim. The Mannheim network had stations across Europe and in North America and Greenland. A number of factors including cost and the Napoleonic Wars contributed to its demise in 1795 as international correspondence, even about the weather, came under suspicion of potential espionage!

In the early 19th century, Francis Beaufort and Luke Howard continued the search for a standard way to discuss weather. Howard was the topic of our last blog post about cloud classification systems, and Francis Beaufort was a member of the Royal Navy. As such, he was interested in trying to classify wind strength for ships at sea. The Beaufort Scale describes the force of the wind based on visual cues, such as white caps on waves or the filling of the ships’ sails. Beaufort also devised one or two letter codes for weather such as “rn” for rain. He used “b” for “blue sky”, which is why we sometimes see “b” as an indicator for “clear” - this is a common symbol found in our own ledgers!

This system worked well enough for the English but as time went on countries wanted to exchange weather data and an international standard was needed. Letter codes for weather conditions based on each country’s language were too confusing. A standard that transcended language was needed.

The first international meeting to set standards for land-based meteorological measurements was held in Vienna in September 1872. Question 15 on the docket was “Is it desirable to introduce for Clouds, Hydrometeors, and for other extraordinary phenomena, symbols which shall be independent of local language, and therefore universally intelligible?” According to the minutes there was a long debate on the “advisability and the difficulty of the adoptions of symbols”, in which scientists from Brussels, Christiania, Geneva, Florence, Vienna, London, Padua, and St. Petersburg took part.

Consensus was met though and the following symbols were agreed upon:


And well, the rest is history! You can see these symbols in use when transcribing the weather data from our ledgers. If you are interested in looking at further weather symbols, check out Meteorological Observations for a full list of symbols you might see while transcribing!

For more information check out:

The Invention of Clouds - Richard Hamblyn
The Weather Experiment: The Pioneers who Sought to see the Future - Peter Moore

Clouds, Cloud Types and Abbreviations

by Victoria Slonosky       on March 13th 2019

Clouds or the lack of, are an ever present part of our skyscape. It is no wonder then that when the classification of the world around us began during the 18th century Enlightenment, with Carl Linne in Sweden developing the binomial system of plant classification (still used today for all living things) that the classification of clouds wouldn't be far behind. The classification began in the early 19th century with Luke Howard.

Luke Howard was a Quaker chemist who spent hours as a boy watching the clouds. He was among the first to realize that clouds had a limited number of distinct types, rather than endlessly drifting from one shape to the next (Jean-Baptiste Lamarck was another who tried to classify clouds by type and height). He based his Latin cloud names on the typical shapes and heights of the clouds. Cumulus clouds are heap-like, stratus clouds by definition and have some form of precipitation falling from them. As they were based on Latin, Howard’s cloud types were able to be used internationally since he first devised them in 1817.

Howard gave his first lecture on cloud types in London in 1802, when he proposed that there were three main types of clouds: Cirrus, Cumulus, and Status. He recognized also that clouds morphed from one type to another, often in recognizable ways as the weather changed. For example, cumulus clouds could spread and merge into a stratus layer. He proposed that the basic cloud formations reflected the physical process by which the clouds were formed, such as cumulus clouds being formed by convection, which turned clouds from mysterious, ever-changing entities into physical sciences which could be studied and related to weather such as participation. In a way, we could say that the classification of clouds launched the scientific field of meteorology.


Thunderclouds gathering - frontispiece of Essay on the Modification of Clouds, 3rd Ed. Luke Howard, 1865

When writing down the observations for clouds in ledgers such as the ones which DRAW is transcribing from, using the full name of a cloud could be cumbersome. Clouds as a result have two letter abbreviations, such as Ci for Cirrus. They can be combined, such as when there is a layer of cumulus clouds to form Cumulo-stratus, Cu-St, or the most impressive of all, the towering thunderstorm clouds which all the way through the atmosphere to the top of the troposphere, Cumulonimbus, CuNi. All clouds with precipitation falling from them are nimbus clouds, so if while transcribing you see an entry for nimbus, check to see if there’s also some precipitation, usually in the form of ran or snow in the same observation time!

If you’re interested in reading more about the history of cloud classification, check out the free e-book of Luke Howard’s Essay on the Modification of Clouds (1865) available here. You can also check out our Meteorological Observations page for a full list of cloud types and their abbreviations!