JAKARTA, Indonesia (AP) — Four Indonesian provinces have declared emergencies in anticipation of worsening forest fires that each year spread health-damaging haze across the region.

The National Disaster Mitigation Agency said Wednesday that emergency alerts in Riau and South Sumatra provinces on the island of Sumatra and West and Central Kalimantan on Borneo will make it easier to mobilize fire-fighting operations and support from the central government.

The agency said satellites have detected 90 "hotspots" or fires across Indonesia, with the biggest numbers in West and Central Kalimantan.

Record Indonesian forest fires in 2015 spread haze across a swath of Southeast Asia and according to a Harvard and Columbia study hastened 100,000 deaths.

Many areas of Indonesia are prone to fires because of the draining of swampy peatland forests for plantation agriculture.