If weather is like the money in your pocket on any one day, climate is like your net worth over time.

I liked this simple analogy to distinguish between weather and climate in a New York Times article by Kendra Pierre-Louis. While there are many causes of extreme weather, keeping this analogy in mind helps keep some overall context even when you’re in the midst of an unexpected cold snap.

Weather and climate: an analogy

Are caused by the Earth’s tilt. As the Earth goes around the sun, the tilt of Earth’s axis — 23.5 degrees — causes at different times of the year, the two hemispheres, North and South, to be either tilted towards the sun or away from it.

In Winter, and closer to the Poles, because light from the sun hits at a greater angle, the solar energy gets spread over a larger area. This makes it weaker, cooler and gives rise to Winter.

In Summer, and closer to the equator, light from the sun hits more directly and so is concentrated on a smaller area making it stronger.

The tilt also means that the number of daylight hours is greater in the Summer than in the Winter, and hence the amount of time it gets heated, which also contributes to the seasons.

Seasons are reversed in the two hemispheres, so if it’s Winter in the Northern Hemisphere it’s Summer in the Southern and vice-versa. The further from the equator you go, the bigger the effect of the seasons. So, temperatures in Ecuador stay relatively constant throughout the year, while the poles experience extremes of 24-hour daylight or 24-hour night and great freezes and great thaws.

PSThis is a correction to my original Seasons sketchplanation which implied that temperature difference was more due to the increased distance from the sun due to the tilt. This is not correct, and it’s taken me, embarrassingly, a long time to right it. Thanks to Adrián Fernández Martínez, marjancek and Reasons2AvoidAndroid for putting me straight. 

Seasons

Nature’s greatest snow machine, where crazy amounts of snow can fall in huge snowstorms on the downwind — leeward — side of a lake. Where the effect is pronounced, such as on the East of some of the Great Lakes in the US, it can generate regions known as snow belts because of the amount of snow they receive.

It works kind of like this: cold air blows over a lake. As the cold air passes over the warmer lake it picks up water vapour from the lake and it warms. This causes it to rise and in turn cool, such that when it reaches the downwind side of the lake it is now a lot of cold moist air which can cause some incredible snowstorms, like 2–3 inches of snow per hour. Satellite pictures like these show it in action pretty clearly. If the land rises after the lake the air can cool faster and increase the effect — and also cause a rain shadow — and if there’s a whole lot of convection and the air is rising fast you can get what’s called thundersnow — a thunderstorm in a snowstorm. I know.

Find weather interesting? Me too. You might also be interested in: Dirty thunderstorms, thunderclouds, yesterday’s weather (applying weather forecasting to software engineering), rain shadow, lenticular clouds, know your cirrostratus from your altocumulus, and British weather.

Lake-effect snow

Caused by ash and rock interacting inside a cloud instead of ice particles. As you can imagine you can get this with volcanoes which can be pretty spectacular. Here’s more about how lightning forms inside a thunder cloud, the regular kind.

Dirty thunderstorm

Thunder clouds are so impressive. Lightning forms due to air currents in the cloud as warm moist air rises up quickly. All the collisions between particles cause different charges to develop between the top and the bottom of the cloud. When that gets large enough, kapow!

Also see: thunderclap or rumble, dirty thunderstorms.

Thunder clouds

I learned about this nice principle from agile software development. Basically, that when thinking about how much you’ll get done next week, what you got done this week is a good proxy. Sure this week was different because you had that external presentation and an offsite, a bug to fix on live and Amy was sick. But the reality is things will interrupt you next week too. Just like the weather, what happened before is a good first guess at what will happen next.

Yesterday’s weather

California is a nice example both stitching up the Central Valley and Nevada. And in Washington State if you need a bit more sunshine, just try driving East.

Rain shadow

Make spectacular photos like these, these, or this, but generally mean high winds high up. Look out.

Lenticular clouds

Stratus: layers AND Cumulus: heaps + height + Cirrus at the very top and you’re a long way already.

Sketchplanations tagged with weather