Access to precise, real-time data about the amount of water in the Sierra Nevada snowpack has become more critical than ever, California water managers say, in order to assist them in making informed decisions about an ever-less-predictable supply of water. That’s why water managers came to a panel discussion about advancements in snow-measurement technology during an Association of California Water Agencies conference in Sacramento last week. The discussion focused on the Airborne Snow Observatory, or ASO program, developed by researchers at the NASA Jet Propulsion Laboratory in Pasadena.