Arctic Clouds: A missing puzzle piece

Ideas we will cover How thick is the atmosphere? The climate system is COMPLICATED Greenhouse gases warm the planet Aerosols cool the planet Clouds can warm or cool the planet (New Vocabulary: Optical Depth) Arctic clouds are warming the Arctic while other clouds are cooling the planet because……….

Thinking about scales How thick would the atmosphere be on my earth ball ? Let’s do a little calculation: Radius of the earth = 6378 km Depth of the atmosphere = 8-18 km Radius of my beach ball earth = 300 mm (30 cm) 10 km x mm = km 300 mm Depth of the atmosphere on my beach ball = 0.46 mm (Find something that is about 0.46 mm thick! Look at the mm marks on a ruler) About 2-3 sheets of regular paper? Note, at the poles, the atmosphere is the thinnest Guesses????

It’s a very complex system!

Greenhouse Gases

Short wave (Solar Energy) Long wave Thermal Heat Short wave (Solar Energy) Long wave Thermal Heat Green house gases make the reflected thermal arrow bigger and WARMS the earth

Aerosols

Short wave (Solar Energy) Long wave Thermal Heat Short wave (Solar Energy) Long wave Thermal Heat Aerosols (smoke and dust make the reflected short wave arrow bigger and COOLS the planet

How do clouds transmit and/or reflect radiation? __________ Do clouds cool down or heat up the Earth’s climate?

Short wave (Solar Energy) Long wave Thermal Heat Short wave (Solar Energy) Long wave Thermal Heat It turns out that clouds can do both. Clouds can make the reflected short wave arrow bigger and COOL the planet, but they can also make the reflected long-wave arrow bigger and WARM the planet

Which cloud effect will win???? WARMER!!!! COLDER!!!!

First question is why can clouds both cool and warm?

Why do these clouds look so different?

Fabulous book by Mark Cassino

Ice clouds pretty, but not very effective at reflecting light or heat

Water clouds are very dense and good at reflecting and absorbing light and heat energy

Question you should be asking……Hey! It’s very cold in the Arctic, why are there ever any water droplets in the cloud? Shouldn’t they be frozen?

This is one of the most surprising discoveries that we started to make only 10 years ago. Arctic clouds are full of layer of “super-cooled” liquid water all year. This is making big changes on how Arctic clouds are considered in the earth’s climate Puzzle. They have a much larger effect on the surface then expected

Long wave Thermal Heat Long wave Thermal Heat Short wave (Solar Energy) Short wave (Solar Energy) Think about what will happen when there is no sun? What effect will win then? Another factor to consider

Clouds can be “umbrellas” or “blankets” Cooler!!!!Warmer!!!!

And the winner is….. In our arctic cloud activity we will look at how an ‘ice cloud” and a “water cloud” change heating and cooling of the surface and speculate about the total effect of clouds is in the Arctic………..

Hint for the activity: The Arctic is very very very very very very very very very very very dark all winter long…………..

Optical Depth is a measure of transparency and is how scientists measure “how thick” a cloud is to light and heat in general, clouds made of snowflakes have lower optical depth then clouds made of water droplets

Thanks for listening……