A cloud opinion poll

Mini-models capture clouds

Why not just make the grid cells smaller?

If current models' grid cells are too big to accurately depict clouds' role in our climate, why don't we just make the grid cells smaller? Well, because it would take way too long and cost too much. Our current climate models can take weeks and months to run on some of our fastest and most expensive computers.

Just make some of them smaller

Researchers at CMMAP have developed a technique in which they make a very accurate computer model that includes high resolution cloud data, but only for a very small area of the grid. The resulting model is small enough that our computers can crunch it, and scientists then apply it to the rest of the world. By using this type of model inside large global models we can bring clouds into the overall picture. It's just like taking an opinion poll without having to call every single person in the country to find out what people think.

So what exactly is a cloud and where do they come from?

3scales: At a large scale, the CMMAP model divides Earth into hexagons of equal size. The model calculations focus on the atmospheric events within each hexagon and, at a small scale, the events that occur along planes within each hexagon.
3scales: At a large scale, the CMMAP model divides Earth into hexagons of equal size. The model calculations focus on the atmospheric events within each hexagon and, at a small scale, the events that occur along planes within each hexagon.Courtesy Lisa Gardiner, UCAR