The NASA Worldview image above shows that there is a large AOD concentration coming off the east coast of Australia. This is due to the many bushfires that are raging along the east coast of Australia. The NSW Rural Fire Service reports that the largest fires are currently contained, but have burned over 180 thousand of acres. The Guardian reports that these fires are often started by lightning strikes.
The NRL/Monterey Aerosol image below shows that the smoke surface concentration created in Eastern Australia reaches above 512 ug/m**3 as shown by the purple blob on the coast of Eastern Australia.