If you’re planning a barbecue, you can now check the mosquito forecast along with the weather forecast. A new tool predicts local mosquito activity, from “low” ranging up to “severe,” for a period of seven days, using an algorithm that processes detailed weather data from Google Earth Engine, the tech giant’s massive satellite imagery database.
“The growth of the mosquito, from egg to a biting adult, is really tied to temperature and humidity…it takes several days to go from one stage to another,” says Jamie Herring, president of Climate Engine, a company that partnered with entomologists at SC Johnson (the makers of Off! brand mosquito repellant, not coincidentally) and Google Cloud to build the tool. “So if we can map the actual temperature and humidity changes themselves, we can use that as a proxy for how mosquitoes would develop.”
The model is “very accurate,” says Maude Meier, an entomologist at SC Johnson, and uses a combination of billions of points of climate data from Google Earth Engine, along with past mosquito population counts from thousands of locations and a scientific understanding of the mosquito’s lifecycle. The team validated it by running the model for previous years and comparing the results to actual mosquito data.
Climate change is boosting mosquito populations in many areas, as hotter weather means that mosquitoes can spread and breed for a longer part of the year. That also means that more people will get sick: Globally, one study predicts that as many as a billion additional people could be exposed to mosquito-borne illnesses like Zika and malaria later this century. In the U.S., mosquito-borne West Nile virus is already widespread, and in some cases leads to severe diseases like meningitis, or even death.
Unsurprisingly, SC Johnson and Off! suggest that people use the mosquito forecasts to arm themselves with more mosquito repellent (the tool is officially called the OFF!Cast Mosquito Forecast, and recommends that people protect themselves and “re-apply protection” every couple of hours when mosquito populations are surging). But it’s also conceivable that someone might use it to decide when to schedule a hike or postpone a camping trip.
The tool could also be used by governments to take wider action, potentially spraying some areas at certain times. “We expect this to be used by communities and public health organizations…that don’t have the resources to do this type of work, which is really computationally intensive,” says Herring. The partners also plan to expand the tool to other countries: Brazil and Mexico may be next.