Abstract：To study the evolution of tropospheric delay during typhoons, based on ERA5 reanalysis data, this paper calculates atmospheric precipitable water vapor of each altitude layer and tropospheric delay during northwestern Pacific typhoon 1822 Mangkhut, 1622 Haima and northwestern Atlantic hurricane(typhoon) 1709 Irma. The results show that there are spatial and temporal differences between the tropospheric delay calculated by ERA5 data and IGS tropospheric delay product. The stronger the influence of typhoon on the station, the more consistency is affected. Further analysis shows that typhoon transits change the precipitable water vapor and its proportion in each altitude layer at the same time, both affecting tropospheric delay. The former is dominant. At a certain amount of precipitable water, the tropospheric delay is the largest when the proportion of water vapor between 850-500 hPa is the largest. Typhoons increase the amount of water vapor distributed in the lower troposphere, so the estimation of tropospheric delay using the traditional tropospheric delay model may produce additional errors.
