Final answer:
Despite stable frequency, the intensity of hurricanes has grown, with Category 4 or 5 storms nearly doubling, leading to more severe weather impacts and higher costs.
Step-by-step explanation:
In recent years, hurricane intensity has increased, which is best illustrated by the growing number of Category 4 or 5 storms. According to the information provided, the number of these intense storms has almost doubled. While the frequency of hurricanes has not seen a significant increase, the strength and duration of the storms have escalated. This intensification in hurricane activity contributes to more severe weather events, leading to increased destruction and higher economic costs.