Author Archives: Walter

Raymond and Jiang (1990): Long-Lived Mesoscale Convective Systems

I still struggle with using potential vorticity (PV) to think about atmospheric phenomena, but many extremely smart people find it very useful, so it’s a good thing to study. PV is perhaps most often used to discuss circulations on very large scales, but there has been a lot of work to make “PV thinking” work for mesoscale circulations as well. This paper describes such a theory to utilize PV to understand the maintenance of long-lived mesoscale systems in which convection plays a substantial role.

Raymond, D. J., and H. Jiang, 1990: A Theory for Long-Lived Mesoscale Convective Systems. J. Atmos. Sci., 47, 3067–3077.
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New Global Temperature Map

I added a map of current surface temperature anomalies from the last 3 months of NASA GISS data on my climate data page. I might add maps of other data sets, but right now NASA seems to provide the “cleanest” in the sense that there is less missing data. I’m not sure if they are just faster with their data processing or if they incorporate more data than other datasets. Either way, the differences don’t bother me much, since the time series of various datasets shows reasonable agreement. Continue reading

NCL: A Tale of Two Titles

When I’m finalizing figures I like to go through and make sure they are adequately annotated. For example, it’s nice to have the units and variable name[s] mentioned somewhere on the plot for the casual reader that’s just skimming through and doesn’t want to take the time read through the figure captions. However, lately I’ve been running into the issue of NCL incorrectly positioning the titles of the x-axis and the colorbar (see example below). Continue reading

Climate Skeptics: Myron Ebell

Myron Ebell is a climate denialist who was recently appointed as an advisor to Donald Trump’s presidential campaign. Ebell’s background is in economics, which explains why most of his thoughts about global warming are about economic policy and not science. But Ebell still claims that the science behind global warming is a hoax perpetrated to harm the US economy. How does a non-scientist get so much credit for trying to dis-credit actual science? Continue reading

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