Something happened to your dog that created a negative association with things in the air. It's not always easy to interpret exactly what happened, but if you want to stop the behavior, you need to desensitize your dog to the things she's baarking at. You can start with a helium ballon to make it easier on yourself and work your way up from there. THe idea is to give your dog a treat BEFORE any negative reaction starts. Once a reaction happens, you are in damage control mode. Sadly, I just dont' have a long time to write out the whole lengthy process of this right now, but there are many great websites that discuss fear issues with dogs and how to desensitize them.
Good luck and I'll try to come back a npost more if you have additional questions.
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Chelle and the rest of the crew including, but not limited to Kita and Taiko (the shiba inu wrestle maniacs), Adi (reserved and dignified tabby cat), and all 28 reptiles