Collectively these homes and factories cover a vast area, further reducing the capacity of the land to absorb rainfall. At the global level, the human influence on the floods is less direct but no less real. The global temperature during the first seven months of this year was the highest of any comparable period on record. Furthermore, the margin of increase over the previous record is itself a record. The month of July is the warmest month since recordkeeping began in 1866.
Higher temperatures mean more evaporation, more intense storms, and more rapid snow melt.
All three could be contributing to the floods. While there is no way of conclusively linking global warming with specific weather events, the likelihood that they are linked has grown with each passing year in which higher temperatures are accompanied by more extreme weather events. That higher temperatures mean more evaporation is certain. And when more moisture goes up, more comes down. Where it comes down is less predictable.