Paleo - an answer befitting a systems engineer. Certainly in a system as complex as our economy there are plenty of stress indicators, particularly for those trained to observe it. In early August of 2008 my aunt, who had some significant Wall Street holdings, was quietly told by her broker to get out immediately. Background levels of system-wide stress, in consistently high oil/gas prices and decreased consumption, have become normal over the past few years. I first learned about the Baltic dry goods index as an indicator of global economic health in 2009 (when both were bad). Perhaps Lloyd's List Intelligence or something similar would be a good lens (though I don't doubt the subscription is pricey). On the consumer side, here in the States, perhaps interest rates aren't a bad warning? The Fed's been doing just about everything it can, bloating its balance sheet, to keep them low for the last four or five years. Now its stated intention is to stop doing that. Interest rates (which it helps to set) are probably a good warning as to what the market's reaction will be. But I'm no economist (and I don't have too much of a clue what the different interest rates are tied to). An actual economist would hopefully have a faster and more reliable marker than that.
On the topic of renewables, according to recent EIA data, the situation in my opinion actually looks good:
with one gigantic caveat: we use petroleum primarily for transportation, and some sectors (like air travel and shipping) aren't susceptible to getting off of it any time soon. We might possibly stand a chance with personal vehicles, but the barriers here are still pretty high. Critical elements like lithium are limited. Cost is a serious constraint. Since I want to pay a house off, I won't be buying a $70+ K Tesla any time soon, and a Volt or a Leaf simply don't have the capability I need. Their range is too short (not even 100 miles)--that's the lot of many folks (not all and maybe not most). Range and capability doesn't even apply to work vehicles like light trucks and anything heavier. Still, reducing oil consumption by moving even part of the market to electric would be helpful--or the bare minimum. And it's precisely this I'm least hopeful about. Until such time as EVs have been viable for long enough, and are widespread enough, that a viable secondary market for the sub-$10K purchasers to realistically think about them (and in today's economy, that's an increasing number of people), then I think their potential is limited (0.37% US market share in 2012). Add to that the charge station build-out which would need to happen sooner than later. Insurmountable challenges? Perhaps not, within 20 years. Within five years, probably.






