1997 Southeast Asian haze

During the peak episode, satellite imagery (NASA/TOMS aerosol index maps) showed a haze layer that expanded over an area of more than 3,000,000 km2 (1,200,000 sq mi), covering large parts of Sumatra and Kalimantan.

[4] Fire is also used during the long fallow rotation of the so-called jungle rubber in Sumatra and Kalimantan to remove most of the biomass, including the woody parts before new plantations are re-established.

After burning out its previous owner, the smallholder or large operator plants their own crops there, gaining de facto control over the disputed land [citation needed].

The smoke haze episode has added to the urban and industrial air pollution in Southeast Asia, causing it to reach alarming levels in many metropolitan areas.

By scattering and absorbing light, the fire-related particulate also resulted in reduced visibility; impairing transportation by air, land and water and seriously affecting the economies of Indonesia, Malaysia and Singapore.