Final answer:
To get a global view of temperature, a scientist could use a thermometer, specifically an infrared thermometer like a pyrometer, which quickly measures the temperature from a distance without direct contact, suitable for global assessments.
Step-by-step explanation:
To get a global view of temperature, a scientist could use a thermometer. Thermometers are instruments designed to measure temperature using materials that expand or contract when heated or cooled. For a more detailed and wide-ranging measurement, different types of thermometers can be utilized, such as alcohol, liquid crystal, and infrared radiation (pyrometer) thermometers.
Infrared thermometers, like pyrometers, are particularly useful for quickly measuring temperature without direct contact. They work by detecting the infrared radiation which increases with the object's temperature. This type of thermometer would be able to measure a wide range of temperatures across different surfaces from a distance, making it suitable for gathering a global view.
On the other hand, barometers measure atmospheric pressure, hydrometers measure the density or specific gravity of liquids, and radiometers measure the intensity of radiation. Therefore, these instruments would not be suitable for measuring temperature.