It's time for the mercury mark to drop and the pollution level to rise. The half hearted bandh may have provided a temporary respite from the smokescreen that clouds overcrowded Calcutta on weekdays, but that is little consolation for a gasping city. Figures released by the West Bengal Pollution Control Board reveal a murky picture against a daily national standard of 200 microgram SPM and 100 microgram/cubic metre RPM, Calcutta this winter recorded levels much higher.