Remote Sensing to investigate Geography & Geomorphology

 HTML: Perplexity AI
Source: "[NYT video] Who are Christof Koettl..." 
Date: 8 September 2026

Former Guardian & twitter now Google data journalist Simon Rogers said “Comment is free, but facts are sacred”, after C.P. Scott's 1921 Guardian motto. Read on for a textbook case in today's New York Times.

click to enlarge, Google Earth screen grab by author

Perplexity AI starts here.

Summary of the video: “Satellite Images Contradict Border Agency on Construction in Big Bend”

The New York Times Visual Investigations team examined Customs and Border Protection’s claim that work on a border-security project in Big Bend National Park, Texas, was limited to “survey and design” activities. Using time-series satellite imagery, the team tracked bulldozers, newly cut patrol roads and vehicle barriers advancing through the park over several months. The visual evidence contradicts the agency’s public statements and indicates that physical construction of border infrastructure was already underway inside the national park.

The video is a useful example of contemporary visual investigation: satellite-image interpretation is combined with reporting to test an official account of what is happening on the ground. It is especially relevant to anyone interested in remote sensing, land-use change and the environmental consequences of infrastructure in protected landscapes.

The journalists

The video was reported and produced by four journalists from The New York Times video and Visual Investigations teams.

• Christoph Koettl is a senior video journalist and satellite-imagery specialist on Visual Investigations. His work uses geospatial analysis to investigate conflicts, border infrastructure and illicit networks.
• Ainara Tiefenthäler is a reporter and video journalist on Visual Investigations. She combines conventional reporting with digital forensics, including video verification, open-source material and satellite images, to investigate conflict, human rights abuses and political violence.
• Luke Piotrowski is a senior video journalist in the Video Operations team. His work includes cinematography and field production for news, enterprise and podcast video.
• Alexander Cardia is a Visual Investigations journalist and producer who works on visual and data-driven reporting, often involving satellite imagery and open-source analysis.

Selected notable investigations

Christoph Koettl

• War crimes in Sudan (2024–2026): Investigations using propaganda videos, witness material and satellite imagery connected commanders of the Rapid Support Forces to executions, arson and sexual violence. The wider New York Times Sudan reporting received the 2025 Pulitzer Prize for International Reporting.
• The Bucha massacre, Ukraine (2022): Satellite and video analysis helped identify the Russian paratrooper unit responsible for civilian killings along Yablunska Street. The wider Ukraine coverage received a 2023 Pulitzer Prize for International Reporting.
• The Kabul drone strike (2021): A visual investigation challenged the U.S. account of an August 2021 drone strike, finding that it probably killed civilians rather than ISIS-K targets. The U.S. military later described the strike as a “tragic mistake.”
• North Korean oil-smuggling networks: Koettl has used vessel-tracking records, corporate documents and satellite imagery to investigate routes by which sanctioned oil reaches North Korea.
• Big Bend border construction (2026): Time-series satellite imagery documented new patrol roads and vehicle barriers in Big Bend National Park, contradicting the border agency’s claim that activity was restricted to survey and design work.

Ainara Tiefenthäler

• The Bucha massacre, Ukraine (2022): Tiefenthäler was part of the team that verified, geolocated and sequenced video evidence in reconstructing the killings of civilians by Russian forces.
• How George Floyd Was Killed in Police Custody (2020): She contributed to the reconstruction built from security-camera video, witness footage and official records. The work was central to The New York Times receiving the 2021 Pulitzer Prize for Breaking News Reporting.
• Peru’s anti-government protests (2023): Reporting and visual evidence documented repeated use of lethal force by Peruvian police and military personnel against unarmed protesters.

Luke Piotrowski

• Video production and cinematography: Piotrowski joined The New York Times as a senior video journalist in late 2025/early 2026. His contribution to major reporting is primarily through field production, camera work and visual storytelling, including the Big Bend border-wall video.

Alexander Cardia

• Visual and satellite-based reporting: Cardia contributes to Visual Investigations reporting on conflicts, security issues and infrastructure, including satellite-based analysis of Iran, border projects and related investigations.

Source video

Watch: “Satellite Images Contradict Border Agency on Construction in Big Bend” — The New York Times