NASA Explorers: The Snow Below | Summary and Q&A

TL;DR

Snow is a vital natural resource in regions that rely on it for drinking water, agriculture, industry, and hydropower. NASA uses remote sensing and airborne campaigns to measure snow depth and water content to understand its impact on climate and for future satellite mission planning.

Key Insights

• 💦 Snow is a crucial natural resource for regions depending on it for various aspects like drinking water, agriculture, industry, and hydropower.
• 🫠 NASA's remote sensing data shows a retreat in snow cover and earlier melting in recent decades.
• 🥺 Measuring snow depth and water content accurately is challenging, leading to the development of airborne campaigns like ASO and SnowEx.
• 🏂 The calibration and testing of sensors and instruments are crucial for accurate measuring of snow under various conditions and environments.
• 🛝 Ground truthing plays a significant role in matching airborne observations with the actual snow conditions on the ground.
• 🫠 Understanding snowpack is vital for water resource planning, as excessive melting can cause flooding, while insufficient snow or premature melting can lead to droughts and longer wildfire seasons.
• 🏂 Long-term monitoring of snow cover is essential for studying climate change impacts on the cryosphere.

Transcript

VO: What we think of snow depends a lot on where it falls. If you live in the eastern U.S., maybe it's fun. Or, maybe it's just a pain. Kim: But if you live in parts of the world where they depend on the water that's in the snow for a large fraction of their total water that they use for drinking, agriculture, for industry or for hydropower, the sn... Read More

Questions & Answers

Q: Why is snow such a critical natural resource in some regions?

Snow provides a significant portion of the water supply for drinking, agriculture, industry, and hydropower in certain areas, making it essential for various aspects of daily life and economic activities.

Q: How does NASA monitor snow cover and changes over time?

NASA utilizes remote sensing to monitor the extent of snow cover in the Northern Hemisphere and has observed a retreat in snow cover and earlier melting in recent decades, indicating potential climate changes.

Q: How is snow depth and water content measured from the air?

NASA's Airborne Snow Observatory (ASO) uses lidar technology to measure snow depth, while SnowEx combines different combinations of sensors like the Snow Water Equivalent Synthetic Aperture Radar and Radiometer (SWESARR) to estimate snow water equivalent.

Q: Why is ground truthing important for snow monitoring?

Ground truthing involves digging snow pits to match the observations from airborne instruments with the actual snow layers on the surface. This helps validate and refine the measurements obtained from remote sensing techniques.

Summary & Key Takeaways

• Snow is essential for water resources in many parts of the world, providing a significant fraction of drinking water, agricultural irrigation, industrial usage, and hydropower generation.

• NASA has been monitoring the extent and changes in snow cover through remote sensing, observing that snow cover has been retreating and melting earlier in recent decades.

• The snow water equivalent (the amount of water in a layer of snow when melted) is challenging to measure accurately, leading to the development of airborne campaigns like the Airborne Snow Observatory (ASO) and SnowEx, which test different sensors and instruments.