American Indian newspaper database

The American Indian Newspaper database (provided, arh, curated?) by Adam Matthews with a UK web address is an awesome collection of American Indian newspapers published over two centuries that is digitally searchable and delivers high res (no pun intended) images of yellowed newsprint.

Anyway.

I did a few simple key word searches - disaster, hazard, emergency - and got this graphic for 'disaster' ...

Any guesses as to why the peak use of 'disaster' in the mid 1980s? (Hint: these are US based news outlets, often collating other news reports, including international).