CONA - Community Observation Networks for Air

In air quality lingo  we normally refer to small areas of increased pollutant concentrations as hot spots  but since this story is about the temperature  field I needed to use something else ... warm spots  will do. As part of the measurement campaign we deployed in Rangiora we not only used ODINs but also four weather stations (like the one on the picture) scattered around the town to explore small scale wind flows and how uniform or otherwise the temperature field is in the area. Before we dive too deep in the analysis, let's pause and look at the two kind of temperature sensors used here. First is the meteorological sites that have thoroughly calibrated and well housed thermometers, protected from the sunshine while the ODIN thermometers were ... well ... not perfectly housed (see image of the inside of an ODIN) and then put in plain sunlight attached to lamp posts (see image of ODIN attached to a lamp post). Now, don't despair! There is a reason why the ODIN tem...

Pretty typical, really! In terms of understanding air quality we’re usually interested in three things: temperature, wind speed and wind direction. Air temperature might tell us something about how much home heating is going on (or it might not – that’s one of the things we want to confirm in this study). Wind speed tells us how much air pollution is going to be dispersed and diluted. Poor air quality in most New Zealand towns usually occurs on evenings when there are a combination of light winds and colder temperatures. Wind direction is interesting because firstly it is linked to wind speed and temperature. For example in Rangiora in winter south-westerly winds are often stronger and warmer and north-easterly winds are lighter and colder. Secondly, changes in wind direction may also tell us if smoke is being dispersed away from the town or just moved around. To find out what the weather was like we will firstly be looking at data from a permanent weather station on the edge of town r...