AERIAL photos of Hay Point Coal Terminal reveal giant black mounds waiting to be transported overseas.
But lately, those mounds have been shrinking.
Last month, based on North Queensland Bulk Ports Corporation records, 1,901,900 tonnes of coal were shipped from Hay Point.
While this may seem like a substantial amount, it was a significant decrease on the 3,116,161 tonnes shipped in August 2011 and less again than the 3,438,350 tonnes shipped in August 2010.
Further north at Abbot Point, the August coal load of 1,434,153 tonnes was slightly up on August 2011, however was still below the 2010 shipment of 1,884,359 tonnes.
It's a similar story at Hay Point's Dalrymple Bay Coal Terminal, with the 2012 August coal shipment of 4,764,366 being well down on the 5,789,302 tonnes shipped in 2010.
CQUniversity resource economist John Rolfe said there were a number of factors contributing to this.)
"The slow down in the Chinese economy is the key factor," Prof Rolfe said.
"It comes on top of a weak United States economy and lots of problems in Europe."
He also said ongoing political tensions between Japan and China could result in future decreases in coal exports.
"The difficulty with that tension is Japan and China are major trade partners," Prof Rolfe said.
"The tension is likely to reduce trade between those two countries... and given they're major importers of our resources that's quite worrying for our industry."