Which of the following methods can be used to estimate long-term heat stress?*1 pointMaximum annual temperatureNumber of days over a critical temperature threshold (i.e., days over 30C)Mean annual temperatureNumber of days over a percentile-based threshold (i.e. days over 95% of long-term average)

All of the methods listed can be used to estimate long-term heat stress.

1. Maximum annual temperature: This method involves looking at the highest temperature recorded in a year. If this temperature is significantly high, it could indicate a potential for heat stress.

2. Number of days over a critical temperature threshold (i.e., days over 30C): This method involves counting the number of days in a year where the temperature exceeds a certain threshold. If there are many such days, it could indicate a high risk of heat stress.

3. Mean annual temperature: This method involves calculating the average temperature over the course of a year. A high average temperature could indicate a risk of heat stress.

4. Number of days over a percentile-based threshold (i.e. days over 95% of long-term average): This method involves counting the number of days where the temperature exceeds a certain percentile of the long-term average temperature. If there are many such days, it could indicate a high risk of heat stress.