*2.1.2 Ozone level*

Increasing levels of ozone (O3) are another significant source of crop yield loss and an existing threat to Asian food security. In East Asia regions there is a significant increase in ozone level that has been recognized as a drastic factor on major crops and trees. Numerous studies document how global and regional yields of staple crops are being reduced by current O3 levels. Due to the increasing level of O3 in the US, the annual cost of edible crop production lost \$4 billion to \$2 billion [7]. Similarly, the total cost It has been estimated that the global loss of wheat, rice, corn, and soybean amounted to \$14 billion–\$26 billion in the year 2000, which is on a par with, and possibly higher than, crop losses presently caused by other aspects of climate change.

Tamburino et al. have discussed the approaches in the scientific literature on the vigorously debated problem of how to feed the world. There seems to be an increasing focus on food production by means of new innovative technologies [8].
