🔍 Key Concepts

• Relative humidity vs. temperature – how full the air is compared to how much moisture it could hold at that temperature • Specific/absolute humidity – how much actual water vapor (mass) is in a given mass/volume of air, regardless of how cold or warm it is • Dew point – the temperature at which air becomes saturated and condensation begins

💭 Think About

• If you cool an air mass but do NOT add or remove water vapor, what happens to how close it is to saturation? • Which humidity terms depend on the actual amount of water vapor present, and which depend on the capacity of the air to hold moisture? • When temperature drops toward the dew point, what generally happens to relative humidity and to the difference between air temperature and dew point?

✅ Before You Answer

• Be clear on the definition of relative humidity (a percentage comparing actual water vapor to the maximum possible at that temperature). • Recall whether specific humidity and absolute humidity change when only temperature changes but the total water vapor content stays the same. • Confirm whether the dew point changes just because temperature changes, if the water vapor content of the air mass stays constant.