"To prioritize and redirect NOAA resources to a focused program of investment on near-term, affordable, and attainable advances in observational, computing, and modeling capabilities to deliver substantial improvement in weather forecasting and prediction of high impact weather events, such as tornadoes and hurricanes, and for other purposes."
Sponsored by the Republican side of the committee, the goal of this act is to provide sufficient resources and guidance to push weather prediction forward more rapidly. And the sponsors are right, with better organization and enhanced resources, weather prediction could improve rapidly in the U.S.. The Democratic side of the committee were clearly unhappy since it is clear that part of the intent of the bill is to rebalance resources in NOAA: more for weather prediction and less for climate.
My take: although this bill has its issues and needs serious revision, I believe that resource allocation has become highly skewed towards climate prediction, to the detriment of BOTH weather prediction and understanding/prediction of climate change. I also believe that a revised bill could be highly bipartisan and a major positive for the U.S. and the world for both weather prediction and climate.
Weather Prediction Versus Climate Prediction Versus Seasonal Prediction
For the sake of this blog, I will consider that weather prediction covers the period from 0 to two weeks. Climate prediction more than a few years out. And there is another animal that is rapidly developing (although skill is modest): seasonal prediction from two weeks to a year out.
Weather prediction is heavily based on numerical weather prediction, in which one starts with a 3D description of the atmosphere and computer models forecast the detailed evolution of the atmosphere.
Climate prediction depends on climate prediction models (also known at General Circulation Models), which are VERY similar to weather prediction models except that the climate models let gas concentration change, use coarser resolution, and are connected to evolving ocean models. Climate simulations are not used to provide a detailed description of the climate at one time, but to provide climate statistics (e.g., winters will be warmer, snowpack will be less, extremes will change in a certain way, etc.). Climate simulation makes use of the fact that changes in "external" forcing--like varying greenhouse gases--will alter the weather patterns over the world. Climate prediction also makes use of long-term cycles (such as the Pacific Decadal Oscillation (PDO) or the Atlantic Multidecadal Oscillation (AMO)).
And then there is seasonal prediction, which really is a hybrid between the two that uses both extended runs of weather prediction models (like the U.S. GFS) and an understanding of modes of natural variability (like El Nino/La Nina). Seasonal prediction also makes use of statistical relationships (such as the relation between snowpack and soil moisture and the weather over the next few weeks and months).
The Imbalance
As described in my previous blogs, there is a substantial imbalance in the resources available for weather and climate prediction and research. For example, the computer resources available for climate is at least one-hundred times larger than for weather prediction (see graphic below):
As a researcher at a leading university that does both climate and weather research, let me assure you it is MUCH easier to get funding for climate research than weather prediction-related research. NSF, NASA, NOAA and many agencies have big money for climate research, while NOAA is constantly zeroing out their funding for extramural weather research (like their CSTAR program). A real eye opener.
The imbalance is profound and large. Does this make sense?
Why Advances in Climate Prediction and Warning Depend on Weather Forecasting
Some supporters of this imbalance argue that climate and weather research are inter-related and thus one should not be concerned about the budgetary issues. That climate and weather research is on a continuum that cannot be divided in any meaningful way. But I would argue that how money is prioritized does make a huge difference and that in actuality the ability to predict the future climate DEPENDS on weather prediction. Let me make the case.
Weather prediction and climate prediction both depend on the same technology: numerical models of the atmosphere. In fact, both the resolution and physics used in climate and weather prediction models are converging rapidly. Weather prediction models are run several times a day and are rigorously verified against a range of OBSERVATIONS. Thus, working on weather prediction allows a cycle of continuous verification and improvement. When you run a climate model into the next century, verification is an obvious problem. And a fact that is often buried is that climate models are often tuned to match the contemporary climate and thus their predictions are suspect.
Bottom line: if you want better climate predictions, you need better numerical models of the atmosphere and weather prediction offers the fastest and most effective route to better models.
The output from climate and weather prediction models are indistinguishable
Weather Prediction as the First Line of Defense For Climate Change
There are many that believe that the weather may become more extreme under global warming (although I think there are a LOT of uncertainties in this assumption). But let us assume that extreme weather events (hurricanes, floods, tornadoes, heat waves, etc.) WILL become more extreme and frequent in the future. What is the first thing you need with more extreme weather? BETTER WEATHER FORECASTS. Good weather forecasts have a huge impact in saving lives and property for extreme weather events, something shown for Superstorm Sandy where about 150 died in a region of tens of millions of people (and many who died did so because they ignored the warnings). So if you care about the impact of climate change, you should be an enthusiastic supporter of better weather prediction.
And if you are interested in the local implications of climate change, the best technology is dynamical downscaling, in which weather prediction models (such as the Weather Research and Forecasting Model, WRF) are driven by global climate models. Thus, cutting edge climate prediction depends on weather prediction models.
The Impacts of Weather Prediction are Large and Certain, while Climate Prediction Impacts are Uncertain
I don't think I have to work hard to convince you that improved weather prediction saves lives and improves the economy TODAY. With trillions of dollars of U.S. economic activity sensitive to the weather, even small improvements can save our nation tens of billions or more a year. The U.S. has some of the most extreme weather in the world and we require state-of-the-art weather prediction to protect our citizens and to aid economic activity. High-resolution U.S. weather prediction is only done by the U.S. government or U.S. companies/universities--the Europeans will not do this for us. But dozens of major groups around the world are doing state-of-the-art global climate predictions for next century. Quite frankly, if the U.S. wasn't doing climate simulations there would still be plenty to choose from and lots of research activities using them. And the skill of such climate predictions are uncertain and few nations appear to be willing to make major economic decisions based on them.
Let me be clear: I believe global warming is a threat to mankind and that research is needed on this topic. But weather forecasting research is certainly equally as important, and in fact serves climate prediction and warning as well.
Bottom Line
The framers of the Weather Forecasting Improvement Act are correct: the U.S. must put more resources into weather prediction research, development, and infrastructure. We have underinvested in weather prediction, with very negative effects on the nation.
The payback on more investment in weather prediction for the nation would be huge. And, it would greatly enhance our ability to predict and warn our nation for any impacts of climate change. If the money existed, it would be nice to greatly increase weather prediction support and leave climate alone. But if resources are tight, the only logical decision is to rebalance our current investments more towards weather prediction.
The current bill needs some work (more on that in a future blog) and I truly hope it can become bipartisan--and it should. Better weather prediction is a win-win situation, both for climate and short-range weather forecasting.
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