Final answer:
The trend in fire frequency, intensity, and total area burned from 1970 to today is influenced by factors such as human activity, climate variability, and vegetation type. Human-ignited fires have resulted in a decrease in forest cover. Fire activity is influenced by climate factors and different vegetation types have different fire regimes.
Step-by-step explanation:
The trend in fire frequency, intensity, and total area burned from 1970 to today is influenced by various factors including human activity, climate variability, and vegetation type. The rise in human-ignited fires has led to a decrease in forest cover over the years. Fire activity is strongly influenced by climate variability, with fire danger calculated based on climate data such as moisture deficit, wind speed, humidity, and temperature. Additionally, different vegetation types have different fire regimes, with grassy environments experiencing frequent fires due to rapid fuel accumulation while rainforests burn infrequently.