Scientists find that change in land cover in Florida's metropolitan areas is affecting the region's local climate. This finding is significant for future urban planning in the state.
Scientists from Florida State University say that land transformation for the past 40 to 60 years is cutting the rainy season by 3.5 hours per year across cities in the state. This change is not observed in rural areas.
Florida Facts: More Forest Areas Are Being Transformed Into Infrastructure
The state's generally mild climate attracts people. Hence, its population has boomed in the 20th century and the number of inhabitants expands at a rate of 20 percent up to 80 percent per decade. Florida's population is expected to reach 23 million by 2030.
Expansion of infrastructure happens simultaneously to accommodate the increasing number of people. Through the past decades, forest and grass areas are being transformed to make way for agricultural, residential, commercial, and industrial development.
The concurrent study, published in the Nature Partner Journal Climate and Atmospheric Science, is pushing previously established theories that land development impacts seasonal climate. To derive this conclusion, scientists used a system that indexed urban land cover on a scale of 1 to 4, with 1 being least urban and 4 being most urban.
The system derives its data from analysis from the National Weather Service Cooperative Observer program, river forecast centers, and the National Centers for Environmental Information. The researchers map the observed correlation between land development and length of the wet season.
"The urban areas experience the same amount of rainfall as the rural areas but in a shorter amount of time. Therefore, the hourly rain rate is stronger in urban regions," explains Vasu Misra, the study's lead investigator and an associate professor of Earth, Ocean and Atmospheric Science, adding that this observation is particularly true during summer months.
To clarify, the scientists have not determined precisely why this happens in Florida's urban areas. Instead, they are suggesting that continuing urban growth in Florida's metropolitan areas will bring shorter and harder rainfall even in the years to come.
Correlation Between Vegetation And Climate
Misra explains that their finding echoes previously established theories that strained vegetation in an area impacts the process of evaporation. Rainwater that would supposedly be recycled into the atmosphere instead becomes an overflow. It had also been observed before that those thunderstorms often split when they land in metropolitan areas.
Misra adds that a previous study has already noted that warmer temperatures in cities result in higher water vapor concentration. Similarly, this occurrence results in stronger rainfall.