A very devastating and long duration wildfire episode occurred in Greece near Athens during 20-25 July 2018. We have investigated particulate matter PM10 and PM2.5; and selected greenhouse gases such as CO2, NO2, SO2, and CH4 which are known to be generated due to the burning of coal, vegetation, and gasoline. There are significant changes in carbon dioxide, methane and carbon monoxide based on the simulations with the chemical transport model. Further, we have checked the ionospheric perturbations during 20-25 July 2018, using the global positioning system (GPS) derived total electron content (TEC) maps over Greece. We have used detrended TEC data to observe the fluctuation in the ionospheric total electron during the presented event. We found that strong ionospheric perturbations have appeared during these events in coincident location to the lower atmospheric anomalies observed in the troposphere and stratosphere. A possible mechanism of the generation of the Atmospheric Gravity Waves (AGW) and Earth’s surface-atmosphere-ionosphere coupling has been discussed. Detrended atmospheric gases/particulate matter density and detrended GPS TEC shows similar variation trend, however, ionospheric changes show significant time delay. This indicates the energy from forest fire region penetrates into ionosphere through the lower atmosphere and gradually triggers fluctuations in the density of the atmospheric elements as well as ionospheric TEC.