Author Archives: Walter

Not that we really needed a new way to see global warming…

Recently Gavin Schmidt tweeted out the figure below, which is a nice way to see the trend associated with global warming in context of the seasonal cycle. It might seem odd that there is a seasonal cycle of global mean temperature, but this is simply due to the fact that there is a lot of dry land in the Northern Hemisphere and a lot of open ocean in the Southern Hemisphere.

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Convective Parameterization Reading list

At a recent conference I was talking to a colleague about research ideas, and we kept coming back to the conclusion that we don’t know as much as we should about how clouds are treated in the various models used around the world. There are many different schemes in use today and most of them are closely related to one another, but it’s hard to keep track of the subtle differences between the approaches. Sometimes it’s hard to find any information about the particular configuration of the convective schemes in certain models. I decided to compile a list of the different types of parameterization schemes, and gather some notes on the key papers that developed these schemes. Continue reading

Cook (2015): Role of Inertial Instability in the West African Monsoon Jump

I find the concept of inertial instability somewhat difficult to grasp. However, it seems to explain some interesting and important atmospheric phenomena, so I’m committed to wrapping my head around it. The current paper is an example of how inertial instability can be used to explain the seasonal behavior of the African monsoon system.

Cook, K. H., 2015: Role of inertial instability in the West African monsoon jump. J. Geophys. Res. Atmos., 120, 3085–3102.  Continue reading

Semantics – Climate Skeptic vs. Denier

In a recent blog post By Adam Sobel, he mentioned that he doesn’t use the word “skeptic” to describe those who do not accept the idea that the earth is warming due to human activity. I had never really thought about my word choice on this issue, but I like his point and many others seem to share this notion. A skeptic has to be open to being proven wrong.

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Matthew Canavan and Healthy Utilization of Uncertainty

I recently read an article by the Gaurdian about the Carmichael coal mine project in Austrailia, which may become one of the largest in the world. There have been several concerns raised about the environmental impact of the new mine, and similar projects to follow in the area. The article focused on the discussion of climate impacts, and it really struck me how well the article portrayed the difficult trade-offs that have to be made when weighing environmental and economic concerns.  Continue reading

CESM: Adding an Idealized Land Mass to an Aqua-Planet

While working on my current research on the African monsoon system, I often wonder about how the monsoon would change if I could reshape the african continent. But to answer this, it would be nice if you could simplify the problem and remove all the other continents. I’ve talked to other people who have similar question about how the Inter-Tropical Convergence Zone (ITCZ) is affected by the existence of land masses. Below are some notes for setting up a model simulation using the NCAR CESM with an idealized land mass for exploring these questions. Continue reading

Benestad (2016): A Mental Picture of the Greenhouse Effect

A recent post on RealClimate.org touched on the question of what is the best simple mental model of the greenhouse effect that should be used to educate the public. Specifically, the author mentions that it is important to consider how convection affects the optical depth, in addition to the obvious role of radiative transfer. This led me to read the more thorough paper by Rasmus Benestad.

Benestad, R. E., 2016: A mental picture of the greenhouse effect. Theor. Appl. Climatol., doi:10.1007/s00704-016-1732-y.

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