Engineers are not scientists. They can be complimentary (scientist explores space, engineer designs telescope, lift vehicle, etc), but are not one in the same.
Since global warming cannot be proven or disproven by conducting experiments, but rather only illustrated by the collection of data, it is theoreticians and not scientists that are behind global warming. Scientists directly involved in the collection of “scientific” data are few in number and not qualified to do anything other than collect and report the data.