get https://api.plume.io/2.0/forecast
| Field | Type | Description | 
|---|---|---|
| timestamp | integer | UTC timestamp 10 digits long. | 
| values | object | List of available pollutants present on the requested location for the given timestamp. Each object key could be any string of NO2, PM10, PM25, O3. | 
| value_upm | float | Concentration measured in µg/m3. | 
| pi | float | Plume Index value corresponding to the concentration of the given pollutant on the given timestamp. | 
| aqi | float | American Air Quality Index value. | 
| aqi_cn | float | Chinese Air Quality Index value. | 
| caqi | float | Common Air Quality Index value (mainly used in Europe). | 
