On 20 July, a wildfire broke out on open mountain ground at Slievenamon in south Tipperary. It burned for ten days before Tipperary County Council confirmed on 30 July that there were no longer any active fire lines, though isolated hotspots remained a risk.
Throughout that period, Sentinel–2, a European Space Agency satellite, captured the fire’s progression across the mountain, providing a clear record of how it spread and where it left its mark. Mallon colleague Sandra Molloy generated the following images tracking the progress of the fire.
Why Satellite Monitoring Matters for Wildfires
Wildfires often start in remote, upland terrain that is difficult and slow to reach on the ground. Satellites monitor these events consistently across their full extent regardless of access, returning to the same area every few days. The images below are false colour composites built from short–wave infrared, near infrared, and red bands. This combination makes active fire fronts and burn scars stand out clearly against the surrounding vegetation.
Tracking the Fire’s Spread
Figure 1: Slievenamon, 13th July
Before the fire began, vegetated areas across Slievenamon appear green — the baseline against which the following images can be compared.
Figure 2: Slievenamon, 20th July
The fire can be seen starting, with the active fire front appearing as bright orange/red against the surrounding land.
Figure 3: Slievenamon, 22nd July
Cloud cover obscures much of this image, but the active fire front is partly visible towards the southeast of the Slievenamon Bog Natural Heritage Area (NHA). The burn scar, appearing dark brown, is also partly visible.
Figure 4: Slievenamon, 28th July
Cloud still covers part of the scene, but the active fire front is now visible in the northwest of the NHA, along with part of the growing burn scar.
Figure 5: Slievenamon, 30th July
With only light cloud remaining along the southern edge, the full extent of the burn scar is almost entirely visible. It extends beyond the boundary of the Slievenamon Bog NHA to the southwest.
Figure 6: Preliminary burn scar mapping, 30th July
This preliminary mapping puts the burn scar at approximately 1,270 hectares (around 12.7 square kilometres).
The Takeaway
Ten days of imagery from a single satellite gave a continuous, remotely gathered record of how the Slievenamon fire spread, from ignition to a burn scar of over 1,000 hectares. That kind of coverage — consistent, wide–area, and independent of ground access — is what makes Earth Observation a practical tool for tracking wildfires as they happen and assessing the damage once they’re out.
Further Information
For further information about the methods used to produce the study and images above, or to discuss your Earth Observation requirements, contact us below.
