Sketchplanations - A weekly explanation in a sketch

Sketchplanations in a book! I think you'll love Big Ideas Little Pictures

Sketchplanations podcast photo of Rob Bell, Tom Pellereau and Jono Hey

Prefer to listen?
Try the podcast

Like Sketchplanations?
Support me on Patreon

Explaining the world one sketch at a time

Two hikers look at distant lightning and count how long it takes to hear the thunder to estimate how far the lightning is away

Flash-to-bang method

How far away is the storm? The flash-to-bang method can help. When lightning is made by a storm the rapid heating and expansion of the air create the thunderclap. But because sound travels slower than light, there's a gap between seeing the lightning and hearing the thunder it produced. Using Distance = speed x time, by counting the seconds from seeing the lightning you can easily estimate how far away it is. Conveniently, the speed of sound in air is about 330 metres/second. So depending on your unit preference: every 3s you wait the thunder travels about 1 km every 5s you wait the thunder travels about 1 mile Give it a try at a safe distance from your next lightning storm. Also see: thunderclap or rumble, thunder clouds, dirty thunderstorm…How far away is the storm? The flash-to-bang method can help. When lightning is made by a storm the rapid heating and expansion of the air create the thunderclap. But because sound travels slower than light, there's a gap between seeing the lightning and hearing the thunder it produced. Using Distance = speed x time, by counting the seconds from seeing the lightning you can easily estimate how far away it is. Conveniently, the speed of sound in air is about 330 metres/second. So depending on your unit preference: every 3s you wait the thunder travels about 1 km every 5s you wait the thunder travels about 1 mile Give it a try at a safe distance from your next lightning storm. Also see: thunderclap or rumble, thunder clouds, dirty thunderstorm

31 Jul 2022

An urban area next to a more natural rural area showing how the urban area gets hotter than the surrounding land

Heat islands

Heat islands are urban areas that can have higher temperatures than surrounding rural areas with more greenery. Heat islands are caused by several factors, including: the types of materials we use in cities for buildings, pavement, and roads that can absorb more heat than natural surfaces such as leaves or grass human additions to the sun's heat, such as air conditioning, vehicles, cooking, or machinery the shapes of our cities that may restrict airflow to carry heat away the mass of our buildings that can absorb heat and release it gradually, even through the night More natural, often rural areas with greenery may reflect more light, release moisture and provide shade. There are ways to help reduce the effect of heat islands, such as planting more urban trees or using green roofs. Deciduous trees have the handy feature of providing shade for a house in the summer while letting light through in the winter when the leaves fall. A study using 2015 data found that "doubling tree cover in European cities could cut the number of heat-related deaths during summer months by nearly 40 per cent." In Columbia's Medellín, creating 30 Green Corridors helped to reduce temperatures by 2°C in the first three years of the program. Learn more about the heat island effect on the EPA site.…Heat islands are urban areas that can have higher temperatures than surrounding rural areas with more greenery. Heat islands are caused by several factors, including: the types of materials we use in cities for buildings, pavement, and roads that can absorb more heat than natural surfaces such as leaves or grass human additions to the sun's heat, such as air conditioning, vehicles, cooking, or machinery the shapes of our cities that may restrict airflow to carry heat away the mass of our buildings that can absorb heat and release it gradually, even through the night More natural, often rural areas with greenery may reflect more light, release moisture and provide shade. There are ways to help reduce the effect of heat islands, such as planting more urban trees or using green roofs. Deciduous trees have the handy feature of providing shade for a house in the summer while letting light through in the winter when the leaves fall. A study using 2015 data found that "doubling tree cover in European cities could cut the number of heat-related deaths during summer months by nearly 40 per cent." In Columbia's Medellín, creating 30 Green Corridors helped to reduce temperatures by 2°C in the first three years of the program. Learn more about the heat island effect on the EPA site.

24 Jul 2022

Happy talk must die

Happy talk is fluff and often self-congratulatory promotional talk, usually intended to be friendly but generally just getting in the way of people trying to get a job done. On the web, and to be honest, in most places, happy talk must die. Brenda Ueland, in her book If you Want to Write, put it perhaps the best I have seen: 'Oh, this over-explaining! It is the secret of all boredom. It is like this: You, the writer, go slowly and laboriously with many words, while the reader gropes through it, saying impatiently: “Yes, yes, hurry, hurry up! I see it—I get it! Go on to the next."' Happy Talk Must Die is a gem from Steve Krug's legendary book on usability, Don't Make Me Think. Here's an excerpt on Happy Talk. Also from Don't make me think: Omit needless words…Happy talk is fluff and often self-congratulatory promotional talk, usually intended to be friendly but generally just getting in the way of people trying to get a job done. On the web, and to be honest, in most places, happy talk must die. Brenda Ueland, in her book If you Want to Write, put it perhaps the best I have seen: 'Oh, this over-explaining! It is the secret of all boredom. It is like this: You, the writer, go slowly and laboriously with many words, while the reader gropes through it, saying impatiently: “Yes, yes, hurry, hurry up! I see it—I get it! Go on to the next."' Happy Talk Must Die is a gem from Steve Krug's legendary book on usability, Don't Make Me Think. Here's an excerpt on Happy Talk. Also from Don't make me think: Omit needless words

17 Jul 2022

Two people walk through many white swans before bumping into a black swan. One claims it was obvious all along.

Black swan events

A swan in Europe was a white swan. So, naturally, swans were thought of as only white by Europeans until news came from travelers to Australia in the late 1600s where black swans are in fact relatively common. Black swan events can turn a worldview upside down. They are unprecedented, unexpected, rare, and with a significant impact. The infrequency of black swan events means prior data about them is too little to reliably guess the likelihood of one, and you may not even think to anticipate the event anyway. Except after the fact, when all of a sudden many people will claim to have predicted it — black swan events are prone to be rationalised in hindsight, believing that all the signs were there beforehand even if they weren't. The idea of black swan events is from Nassim Nicholas Taleb. He writes: "One single observation can invalidate a general statement derived from millennia of confirmatory sightings of millions of white swans. All you need is one single black bird." Examples Taleb gives include the September 11 terrorist attack, the 2008 financial crisis, World War I, or the rise of the Internet. More Taleb sketches: on mistakes, the firehouse effect, and the Lucretius problem. Also, hindsight bias.…A swan in Europe was a white swan. So, naturally, swans were thought of as only white by Europeans until news came from travelers to Australia in the late 1600s where black swans are in fact relatively common. Black swan events can turn a worldview upside down. They are unprecedented, unexpected, rare, and with a significant impact. The infrequency of black swan events means prior data about them is too little to reliably guess the likelihood of one, and you may not even think to anticipate the event anyway. Except after the fact, when all of a sudden many people will claim to have predicted it — black swan events are prone to be rationalised in hindsight, believing that all the signs were there beforehand even if they weren't. The idea of black swan events is from Nassim Nicholas Taleb. He writes: "One single observation can invalidate a general statement derived from millennia of confirmatory sightings of millions of white swans. All you need is one single black bird." Examples Taleb gives include the September 11 terrorist attack, the 2008 financial crisis, World War I, or the rise of the Internet. More Taleb sketches: on mistakes, the firehouse effect, and the Lucretius problem. Also, hindsight bias.

10 Jul 2022

Only dead fish go with the flow

Only dead fish go with the flow. To me, this is a nice reminder to swim your path in life and be true to yourself. I heard about this from Patricia Ryan Madson in her book Improv Wisdom, and she, in turn, saw it in a Welsh pub. "To reach a port we must sail. Sail, not tie at anchor. Sail, not drift." —Franklin D. Roosevelt…

3 Jul 2022

The cost of fixing bugs

Just as mistakes and the unexpected are part of life, bugs are part of software development. In general, the longer the time between when a bug was first introduced and when the bug is identified and fixed the more expensive it is in both time and money. It might go something like this: If you spot a bug as you're writing a new feature everything is fresh in your mind and it can sometimes take just a moment to fix. If a bug turns up later or perhaps soon after it's deployed you might have an idea of where it might be and track it down fairly quickly. If a lot of time has passed since a feature was worked on and a bug is spotted or tackled then it might take a fair bit of time to figure out how everything works again before you can fix it. And if a really long time has passed then, aside from the cost of interrupting what you are otherwise working on, it may not even be clear what was intended by the original code, probably written by others, and there's a fair chance more has been built on top of the buggy code making it more complex and a bigger task to tackle. The only way to solve it may be stepping through and figuring out behaviour slowly and steadily line-by-line. You could probably replace 'bugs' with 'code' 'problems' or 'mistakes' in most scenarios. Aside from it matching my experience, Joel Spolsky gives a nice explanation in his classic article The Joel Test.…Just as mistakes and the unexpected are part of life, bugs are part of software development. In general, the longer the time between when a bug was first introduced and when the bug is identified and fixed the more expensive it is in both time and money. It might go something like this: If you spot a bug as you're writing a new feature everything is fresh in your mind and it can sometimes take just a moment to fix. If a bug turns up later or perhaps soon after it's deployed you might have an idea of where it might be and track it down fairly quickly. If a lot of time has passed since a feature was worked on and a bug is spotted or tackled then it might take a fair bit of time to figure out how everything works again before you can fix it. And if a really long time has passed then, aside from the cost of interrupting what you are otherwise working on, it may not even be clear what was intended by the original code, probably written by others, and there's a fair chance more has been built on top of the buggy code making it more complex and a bigger task to tackle. The only way to solve it may be stepping through and figuring out behaviour slowly and steadily line-by-line. You could probably replace 'bugs' with 'code' 'problems' or 'mistakes' in most scenarios. Aside from it matching my experience, Joel Spolsky gives a nice explanation in his classic article The Joel Test.

26 Jun 2022

Search·Categories·Archive