And nobody is there to get thirsty, does it make any noise? It seems obvious now in retrospect, but the risk of major [perceived] droughts is much higher simply because water demand is so much higher.
As humans flocked to warm sunny places to live - aided by air-conditioning - the problem of water supply was not enormous to begin with. But as their mass has gone demographically and economically critical, being places with large populations make them more likely to be places where people would find jobs, entertainment, etc.
Consequently, even mild droughts will be felt as major events since more lives will be impacted.“The 2002 drought in Colorado was reported by the media and by public figures, and even by a national drought-monitoring agency, as an exceptionally severe drought. In this paper we examine evidence for this claim. Our study shows that, while the impacts of water shortages were exceptional everywhere, the observed precipitation deficit was less than extreme over a good fraction of the state. A likely explanation of this discrepancy is the imbalance between water supply and water demand over time. For a given level of water supply, water shortages become intensified as water demands increase over time.
The sobering conclusion is that Colorado is more vulnerable to drought today than under similar precipitation deficits in the past.”
My recommendation to the Northern Colorado Water Conservancy (and others that work with managing water resources), is the following:
With today’s and future scenarios of population, infrastructure and demand,
1. estimate the consequences if another historic drought such as in the 1930s or 1950s reoccurred;
2. estimate the consequences if a paleodrought, such as the megadrought of the 16th century, reoccurred;
3. estimate the consequences if a sequence of years with the driest conditions would happen.
Then the threats due to these events, all of which have actually happened, can be used to provide guidance to policymakers as to what should be done if these dry periods occur in the coming decades.
The global model projections can the be folded into those studies, to satisfy those who conclude they have skill, in order to ascertain if they produce droughts that fall outside of the assessments under #1 through #3.
This approach is a more robust and inclusive approach than by relying on the global models as the tool to use for planning. The costs of using the global models as the assessment tool should be redirected to these other assessment approaches given by #1 through #3.
I do agree that we should plan for long term drought even if the models fail in their predictive skill and we have wet periods in the coming years. We know that in the arid and semiarid western United States, long term drought is part of the system even if humans were not altering the climate. [More]
I am still watching the Atlanta event for a paradigm shift in urbanization.
But, according to state climatologist David Stooksbury, even with divine intervention, the long term forecast is not so good.
He told me: "The concern is right now is that we have entered a La Nina climate pattern. Historically, that has meant a warm, dry winter - beautiful golf weather, but terrible if what you need is rain to charge the system.
"So there is a good possibility that we will not receive enough rain to recharge the hydrological system to get us through next summer."
And what happens then, I asked him?
He paused. "We're going to have to make some much more dramatic conservation. Going from annoyance, to actual change of lifestyle." [More]
Depending on how this water shortage plays out (and it's not going particularly well right now) we could see significant changes in how growth is regulated. And there will be immense pressure to revamp our arcane and arguably outdated water laws.
Not a good thing for the #1 (70%) user of fresh water on the planet.