Here's another possible reason why you're smelling that smoggy haze-like in the air these days — according to the Singapore Civil Defence Force (SCDF), there were a total of 94 wildfires that they put out this month alone.
121 vegetation fires occured across Singapore so far this year, with the bulk of them taking place in March. The biggest case was the one at Yishun Ring Road on March 2, where blaze spread the span of five by 10 metres and took an hour for firefighters to put out.