1) Demoralizing 2) Disastrous 3) Loud 4) Overwhelming 1) Loud 2) Revised the ratings 
[agriculture] In the history of crop domestication, several important advances have involved a mutation in a crop plant that reduced shattering — instead of the seeds being dispersed as soon as they were ripe, the mutant plants retained the seeds for longer, which made harvesting much more effective. A particularly important mutation that...[machine learning] Nogger, own photo, fair use. ...
• (p. pr. & vb. n.) of Shatter
[adj] - seemingly loud enough to break something
adjective seemingly loud enough to break something; violently rattling or clattering; `shattering rain striking the windowpanes`; `the shattering tones of the enormous carillon`; `the shattering peal of artillery`