Scuba allows the scientist to set up the experiment and be present to observe unforeseen alternatives to the hypothesis.
The field of global change biology includes investigation of evidence relating to global warming and ocean acidification.
Training standards vary throughout the world, and are generally higher than for entry level recreational diving, and in some cases identical to commercial diver training.
There are a few international agreements that facilitate scientists from different places working together on projects of common interest, by recognising mutually acceptable minimum levels of competence.
Many of the measurable changes in global climate occur in the sea.
Coral bleaching is an example of an indicator of change, and scuba diving has provided a large amount of low-impact observational data contributing significantly to the large body of knowledge on the subject over several decades.
Scientific diving is any diving undertaken in the support of science, so activities are widely varied and may include visual counts and measurements of organisms in situ, collection of samples, surveys, photography, videography, video mosaicing, benthic coring, coral coring, placement, maintenance and retrieval of scientific equipment.
Underwater diving interventions, particularly on scuba, provide the capacity for scientists to make direct observations on site and in real time, which allow for ground-truthing of larger scale observations and occasional serendipitous observations outside the planned experiment.
The field of ocean acidification and the impact of anthropogenic carbon dioxide emission has seen similar growth and most of the cited articles in this field have relied to a significant extent on data collected during scuba diving operations.
The field of paleoclimate reconstruction has a major influence on the understanding of evolution and the ecological and biogeographic past, as climate is the most powerful driver of evolution.