This report only goes through part of 2012, since then the release emissions of green house gas has been really increasing. The increase is for a couple of reason, first was the global recession which was probably the cause of the greatest green house emissions reduction in recorded history the second is Japan has switch to power generation with a high greenhouse gas generation. With an increase already from power generation switch and with the economy now coming back the minor decrease they made will soon be gone.
However the main method that Japan reduced the Kyoto number was by paying off organizations and groups in the form of carbon credits and by planting trees. Alot of the trees being planted are in places destroyed by natural disasters so a big bonus for them.