Emission inventories for SO2 and NOx in developing country regions in 1995with projected emissions for 2025 according to two scenarios.

Top-down inventories of anthropogenic SO2 and NOx emissions were compiled f or 1995 for developing country regions. Regional emission factors were used to generate two sets of projected emissions for 2025. For the first set, r egional emission factors were calculated assuming no further improvements i n emission control over 1995 levels whereas for the second it was assumed t hat, by 2025, controls converge to the 1995 average levels for OECD countri es. Without further improvements in emission controls, 2- to 4-fold increas es in SO2 and NOx emissions are projected for developing country regions by 2025. Asian emissions would be particularly high with SO2 and NOx emission s projected to increase to 30.7 Tg S yr(-1) and 8.8 Tg N yr(-1) respectivel y in the 'China+' region (China, Korea (D.P.R.), Laos, Mongolia, Vietnam) a nd 18.6 Tg S yr(-1) and 8.5 Tg N yr(-1) in South & Southeast Asia. Mapping these emissions shows that the increases would be concentrated in eastern C hina, Taiwan and the Republic of Korea. Technological convergence of emissi on controls in developing country regions would lessen the projected emissi ons by 14% to 30% for SO2 and by 10% to 20% for NOx. A faster rate of emiss ion control convergence and/or increased use of emission prevention approac hes will be required if the 1 1/2- to 3-fold increases in SO2 and NOx, emis sions projected under the convergence scenario are to be avoided.