Monday, September 14, 2015

Global Temperature Rise, how much is there, really?

How much has the global temperature risen?

If I showed you this image, how would you explain it?

Figure 1: Note - the temperature values are within the margin of error value discussed in Heat Island Effect
 (National center for Atmospheric Research, 2015)

In my last essay, I discussed the impacts that the Heat Island Effect has on climate due to the high bias in reporting and recording. Before going further, it’s important to take a moment to discuss some terms and phrases:
1.       Climate – climate is a normalized (averaged) numerical value given to a location on early over the span of 30 years. Climate is often defined as “weather conditions over a long period of time”. That’s untrue if you work in climate or meteorology – it is an average representation of the weather conditions in 30 year increments.

2.       Climate Change – Climate can’t really change since it isn’t an actual event. Climate data can be used to forecast trends, but climate is a record, by its very nature, and therefore can’t be changed, and changing it would only change our interpretation of past events.

3.       So what is Climate Change?
Climate change is a title we give to variations on synoptic or macro-scale (large scale) weather patterns over time. We use temporal meteorology (what’s happening today in the weather) and compare it to climate to our records. If it is above or below the average, then it can be said that unusual or unpredictable patterns are occurring.

4.       How long have we been recording weather data? The first known weather recordings were taken by Rev. John Campanius Holms (National Oceanic & Atmospheric Agency, 2007), in 1644. However, it wasn’t until 1891 that there was a network of weather stations capable of recording enough data for climate. That gives us 124 years of weather recording, which gives us 4 sets of 30 year climatological data.

5.       Why are you telling me this?
Short answer: Those first recordings in 1644 were well within a period of time called the Maunder Minimum which decreased temperatures between 1 and 2 degrees Celsius, Globally (Drew Shindell, 2001). If we know we are starting off in a period of marked cooling, such as the Maunder minimum, a rise in temperature globally, of 1-2 degrees Celsius is negligible.

6.       But… climate change.

Yes, and it’s anthropogenic. I’m not arguing that it isn’t, but we need to cut through the hype to get to the science, and the first step in doing that is understanding what temperatures get recorded, and how they’re used.
Using climate to forecast weather is like using a car to drive an engine. Neil deGrass Tyson has used his “dog walking” analogy (Tyson, 2014) to describe this: Loosely, he states that weather is like the dog, while climate is like the dog’s handler – the dog varies its path but is ultimately controlled by its handler.
This fallacious argument is easy to contest, using the points above. For one, the dog doesn’t “create” the person walking it as weather creates climate.

Second, and perhaps most importantly, Climate is used to “forecast” global trends. In this analogy, it would be as if the dog was weather, and the person wasn’t walking him at all, but rather saying, “Well, this is where he went, so this is where I think he will go based on where he has been”.

Third, and this is the point I hope to emphasize in this essay: We don’t use the information about where the dog has been. NASA has used paleoclimatology to assess the climate for the last 800,000 years, and we are reasonably confident when we quote the IPCC that the last 125 are sufficient to make an educated guess. That is us making a guess with 0.00016% of the available information. Would you feel confident making a guess at something if you 99.9984% of the information was still utterly unknown to you?

So, knowing what you know now, how would you explain the following image depicting past Paleoclimates on Earth (Riebeek, 2010)?

Given that our ability to take accurate measure, and make semi-accurate predictions of meteorological conditions is roughly 125 years old, how can we argue that the projections we have now are complete and accurate enough to direct public policy?
Because, while we can see these trends have indeed played out before, and the speed at which the warming is occurring is significantly faster than in most of these other periods, and is predicted to continue at approximately 20 times the rate it has occurred in the past (Riebeek, 2010), and more important is the interface between warming trends in the global climate and the emergence of a human population continually demanding more resources.

This is the true story of Climate Change, and the one that no one wants to talk about. How do we, as a species, continue to make room for a population that will double by the end of the century when we have so many living in poverty now? What environments will be sacrificed on the altar of growth?


Cheers,
Aaron

3 comments:

  1. Where does GIS fit into the climate change research and discussion? Is it useful mapping things like changes in ocean temperatures and currents, etc? It seems like it would help take the discussion away from the line chart of global temperature and CO2 that everyone is so familiar with seeing and may make it more tangible when it is on a map.

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  2. Where does GIS fit into the climate change research and discussion? Is it useful mapping things like changes in ocean temperatures and currents, etc? It seems like it would help take the discussion away from the line chart of global temperature and CO2 that everyone is so familiar with seeing and may make it more tangible when it is on a map.

    ReplyDelete
  3. GIS, especially in conjunction with LIDAR and satellites which read surface heating, can better direct our attention towards the relative heating across areas. This would be significant considering that our current methods rely on taking readings at geographically dispersed stations and smoothing the average numbers before sending them off to become part of the aggregate climate data.

    More accurate readings could give use better information for our models, and interpolation on GIS maps could illustrate how regional effects differ from one another. It would largely validate what we already suspect, but could also improve our modeling with more accurate information.

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