Why Observe?: Land Cover

Summary

The video highlights the importance of land cover observations and citizen science through the GLOBE Program. It features scientists, such as Peder Nelson and Eric Brown de Colstoun, who use satellite imagery to map and study the Earth's landscape. Citizen scientists contribute by providing ground-truth data, helping to improve the accuracy of land cover maps. These observations assist in tracking environmental changes, such as deforestation and urbanization, and predict future climate impacts, including flooding. The video encourages participation in the GLOBE Observer app to help monitor and protect the environment.

Takeaways

• 😀 Peder Nelson’s career began in 2002 with the Biscuit Wildfire, the largest wildfire in Oregon’s history.
• 😀 Satellite data became essential for mapping the effects of the wildfire and understanding the land cover changes.
• 😀 Citizen scientists play a crucial role in filling gaps where satellites can't reach, helping traditional scientists gather better data.
• 😀 The GLOBE Program allows people worldwide to participate in land cover data collection and contribute to scientific research.
• 😀 Land cover refers to the physical characteristics of the Earth’s surface, such as forests, deserts, or urban areas.
• 😀 Satellite images use pixels to represent land cover types, with each pixel covering an area of 30 to 500 meters squared.
• 😀 Ground-truthing is vital to verify the accuracy of satellite imagery and improve land cover maps.
• 😀 Land cover maps help track environmental changes, such as deforestation and urbanization, which can affect climate and ecosystems.
• 😀 NASA’s models simulate interactions between Earth’s systems and use land cover data to predict future environmental conditions.
• 😀 Urbanization increases impervious surfaces like concrete, which can alter water flow and increase flooding risks.
• 😀 Participating in the GLOBE Program allows citizens and students to contribute valuable observations that support scientific research and environmental monitoring.

Q & A

What was Peder Nelson's role in the early stages of his land cover career?

Peder Nelson's career in land cover began in 2002 with his involvement in botany surveys, where he focused on identifying rare plants and mushrooms. He spent a lot of time in the forest documenting these species.

How did the Biscuit Wildfire affect Peder Nelson's work?

The Biscuit Wildfire changed Peder's work significantly. The fire required him to map the areas affected by the blaze, including those he had visited recently. It also prompted a shift towards using satellite data to track the fire's impact across a vast area.

Why is satellite data crucial in land cover mapping?

Satellite data is crucial for mapping land cover because it allows scientists to observe large areas that are difficult or impossible to reach on the ground. It provides a broader perspective and helps monitor changes that would be hard to track through fieldwork alone.

What role do citizen scientists play in land cover observations?

Citizen scientists help by taking land cover observations, providing valuable ground-truthing data that verifies and complements satellite imagery. Their input is essential for filling in gaps where satellites may not capture detailed information.

What is land cover, according to Dr. Eric Brown de Colstoun?

Dr. Eric Brown de Colstoun defines land cover as the basic form of the landscape, such as forests or deserts. It refers to the visible surface features that can be studied from space using satellite imagery.

How do pixels work in land cover imagery?

Pixels in land cover imagery are the smallest units of a digital image, representing a specific land cover type. Each pixel corresponds to a certain area on the ground, and when combined, they create a map of the land cover.

What is the significance of ground-truthing in land cover mapping?

Ground-truthing involves verifying satellite data by taking observations on the ground. This is essential because satellites cannot always capture everything, such as what lies beneath tree canopies or cloud cover.

How does urbanization affect land cover and water flow?

Urbanization changes terrain and surface characteristics, leading to the creation of impervious surfaces like concrete. These surfaces prevent water from soaking into the soil, which can alter water flow and increase the risk of flooding.

Why is it important to study land cover changes over time?

Studying land cover changes helps scientists understand environmental trends, such as deforestation or urban expansion. These observations are crucial for predicting future environmental conditions and their impact on ecosystems and human communities.

How does land cover data help scientists predict future environmental conditions?

Land cover data provides essential inputs for models that simulate the Earth's systems, including climate and weather patterns. By understanding current land cover, scientists can predict future changes, such as the effects of climate change or urban growth.