 My research is in the area of urban climate, so looking at temperature observations across urban areas and trying to quantify the urban heat island magnitude. So that's temperature difference between urban areas and rural surrounds. We looked at some longer term temperature trends in Hong Kong between the urban area and the rural surrounds. On some days, some hours of the days, I particularly found that we were getting temperature differences of up to 12 degrees Celsius. It's very, very different. Urban areas are warmer than rural surrounds and it's called urban heat island because it tends to show up sort of like an island of heat if you think of a city that you have urban areas and then perhaps grasslands pastures surrounding it and you get this island of heat in the middle. Does the measurements in the city, does that affect like a regional temperature record? If you're looking at sort of climate change and sort of global climate change and wanting to know how greenhouse gases are affecting their climate, then temperature records from stations in the middle of the cities are usually not included. It's stations that are not under any influence of urbanization because you wanted to want to just look at influences of sort of other forcings, not urbanization. The data I look at is in that I'm actually interested in the urban measurements but those that are particularly interested in global climate change then they'll either look at the data that's from non-urban areas or homogenized data sets. It needs to be understood that there's a lot of work that's done under developing these data sets that are just purely to be looking at global climate change without the impacts of urbanization and so there's papers, documents galore that you can read about this where you can see that they look at each individual site and they'll look at any outside influences and they'll discard sites which have moved in time or which have got a significant urbanization impact on them. So yeah it's not just taking every site in the world and looking at how the temperatures change.