The Syrian Observatory for Human Rights recorded 931 government airstrikes and 1,083 barrel bombs on towns across Syria in the first month of 2015.
At least 271 civilians were killed, including 50 children and 37 women, while at least 1,000 were wounded.
The regime first used its warplanes in the Syrian war in July 2012.
Syria's uprising started in March 2011 with anti-government protests later turning into a civil war pitting a range of rebel groups against the military.
According to the UN, at least 220,000 people have been killed since the war broke out, while at least 9 million others have been displaced.