In order to assess and quantify how much greenhouse gas is emitted from the Greater Toronto Area (GTA), a two pronged approach is used. Previous studies have developed facility-level inventories for greenhouse gases in the GTA. In order to validate these inventories, in situ measurement and remote sensing are useful for evaluating and improving these estimates. This talk details plans for expanding our current GHG measurement capacity. The new Helios-100 low-resolution FTIR spectrometer, and sample data from the instrument, are presented. In situ measurements of methane plumes from sources in Toronto are shown, and the challenges of data processing are also discussed. Finally, I discuss work towards developing a low-cost methane sensor network capable of filling in the measurement gaps from some of Toronto’s least well constrained methane emitters.