CREATE TABLE table_22854436_1 (average_annual_rainfall__mm_ VARCHAR, population__2002_census_data_ VARCHAR)

Name the annual rainfail for 2002 population being 493984
SELECT average_annual_rainfall__mm_ FROM table_22854436_1 WHERE population__2002_census_data_ = 493984
SELECT "average_annual_rainfall__mm_" FROM "table_22854436_1" WHERE "population__2002_census_data_" = 493984