william: balsari's partner in this work is dr., a harvard professor of epidemiology. caroline: a lot of the ways that we are conceiving of the issues of climate change are from large global models, remote sensing data from satellites and things like this. and the scale of which we're talking about the problem is often too large. so we don't have that granular human scale data to understand the impacts of climate change. william: getting better data is critical. knowing who is most affected could trigger insurance payments, disaster declarations and more. for balsari, hurricane maria, the storm which devastated puerto rico in 2017 was a crystal clear example of a climate driven disaster impacting human health. >> caroline buckee and i were involved in a study. while the initial government estimates were that about 64 people had died, the study suggested that the true mortality was closer to about 4,000. they didn't die on the day of the landfall. they died for months of disruption to other aspects of their lives. william: disruptio