A 2" speaker might not give a high volume of sound at more than a few yards range in the great outdoors. In the old days of hifi, if you moved a speaker out of a corner, you could reckon on doubling the power input needed, move it away from a wall, double again. Outdoors, anybody's guess, but another doubling would seem good. I got good results with a similar size speaker doing a warship "whoop" at over 50 yards if it was quiet, but if I had been going for an engine sound, what with it being continuous, a bigger speaker would have been needed. Remember that for a given perceived sound level, the lower the pitch, the bigger the area of the speaker required. Also for continuous sound, you need to derate the amp to avoid overdriving it.
40 yards is about 1 mile at 1:48, so when you consider the distances at which the various sounds will be heard, that might be a consideration as well.