Long Term Decreasing Rainfall in the West

If you are in the American Southwest of Northwestern Mexico, the chart above ought to wake you up. While on Adjunct Faculty at SDSU College of Sciences, P.I. at SDSURF, I studied the White Mountain Dendrochronology data and produced this chart of 7996 years of paleoclimatology rainfall data.

The data has a 20 year Gaussian filter to reduce the "noise" from the annual changes in rainfalls which can be quite dramatic and confuse the overall trends. To give a brief idea of this, the chart below would look a lot more like the chart above without the filter.

What is missing from this seven millennium of data is rhetoric of any group suggesting they have short term answers for a global issue of this duration. This is pure science, hard data. Ignore this at your own peril, and these is only one solution for diminished rainfalls: Make water, and do it soon, we are well into this crisis.

Just for now, suspend your thinking about CO2 reduction being the solution. That is not the issue. This is seven millennia of data and shows very long rainfall trends from this location, and directly implies those patterns for the region. Weather events are synoptic in scale, not localized events. It is valid to claim that rainfall totals in this one central California location directly implies rainfalls in the region.

This is itself not a political issue. All political persuasions are affected by this regardless of whether you are left, right, up, down, or sideways, the climate does not care. The climate is nonpartisan.

The next chart zooms all the way in to the last 200 years of available data, shown on the chart above as the last orange down trending arrow.

Here, we can see the downward trending rainfall totals and this just touches on the very long downward trending we can expect in the west.

This is also generally accepted by the western states as a basis for action when we see both population growth and also diminishing rainfalls.

The western region of this continent can look forward (not in the enjoyable sense) to several hundred years more of the current downtrend in rainfall before the slow trend change and a similar slow rise in rainfalls before returning to what is falsely referred to as "normal" rainfall totals sometime about the year 2500.

We will see more plants that use C4 and CAM photosynthesis throughout the region because of this reduction in rainfall. These forms, as opposed to C3 photosynthesis use less water and use it more efficiently.

The good news is, the technologies are currently available to solve the water crisis. The bad news is, this is expensive, and so governments will need to reduce spending to solve this very real problem that is not going away.