There’s something in the water. It’s oil. On boats. That isn’t good if you’re betting on prices to rally.

In its latest monthly report, out Tuesday, the International Energy Agency mentioned that some oil at European and Asian trading hubs was now being stored on vessels, despite prices not really justifying the cost. The implication is that regular storage tanks are getting a tad full.

With oil prices having traded in a band between roughly $40 to $50 a barrel for about three months, some prominent voices say that the bottom is in. Granted, that “some” includes OPEC ministers, for whom predicting a rebound in prices is a little like Ronald McDonald forecasting a bull market in hamburgers. Still, with global oil demand projected to be up by a hefty 1.8 million barrels a day this year, and with low prices clearly starting to eat away at the U.S. shale boom, the foundations of a recovery are coalescing.

The IEA’s comments on storage constraints, though, should serve to remind investors that this isn’t 2009 all over again. Back then, in the aftermath of the financial crisis, when oil last paddled in the shallow waters of $40 or less, it surged back above $80 in less than a year and hit triple digits again by early 2011.

In hindsight, a few things explain that remarkable recovery. One was the defibrillator applied to the global economy by massive stimulus spending in the U.S. and China. In April 2009, the International Monetary Fund was forecasting the global economy to shrink that year and expand by a meager 1.9 percent in 2010. As it turned out, global GDP actually rose slightly in 2009 and surged by 5.4 percent the next, with emerging markets -- the bedrock of the commodities supercycle -- at the vanguard.

OPEC, meanwhile, helped on the supply side, slashing output by just over 5 million barrels a day between July 2008 and April 2009. Libya’s collapse into civil war provided the final push back above $100 in 2011.

None of these supports exist in the same way today. The IMF just trimmed its growth forecasts for this year and next to a relatively sluggish pace of around 3 to 3.5 percent, with risks to the downside.

Might the economists be too pessimistic? Sure, but given China’s slowdown, it’s difficult to see Beijing providing the same jolt to prices this time around. While the country’s latest trade numbers indicate crude oil imports are up around 10 percent year-to-date compared with the same period in 2014, a sizable chunk of that looks like stock building while prices are low. Meanwhile, the country’s net exports of refined products -- the fuels we actually use -- continue to expand.

Supply dynamics have also turned upside down. Next month will mark the first anniversary of that fateful OPEC meeting where kingpin Saudi Arabia nixed any idea of a cut to output. It has added about 750,000 barrels a day of supply since then for good measure, as it seeks to fend off competition from the likes of Russia and the anticipated extra supply from Iran as and when sanctions are lifted.

The latter development, especially, promises to keep oil subdued in 2016, all else equal. IEA projections imply that that, with incremental supply from Iran factored in, global inventories of oil will keep expanding through the end of next year. If so, that would mark 12 consecutive quarters of excess oil flowing into storage, something not seen since the IEA’s data series began in 1986. According to these projections, inventories will have increased by 1.35 billion barrels since the start of 2014, roughly equivalent to two new U.S. Strategic Petroleum Reserves.

Remember that it is refiners, not consumers, that buy crude oil. Thus far, refiners have been happy to take cheap barrels and turn them into products like gasoline and diesel, even if some of those extra gallons end up in storage tanks or, as it seems now, on boats. For example, while U.S. crude oil stocks have fallen by around 30 million barrels since this year’s peak in late April, inventories of refined products have simultaneously swollen by 90 million barrels.

So the crude glut is becoming a fuel glut. And as that starts to weigh on profit margins for refiners, the first cost they will seek to cut is that of their main raw material: crude.

(This column does not necessarily reflect the opinion of Bloomberg LP and its owners.)

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