Published: June 12, 2023
Mark Williams

We are very sorry to pass along the news that Mark Williams, Professor Emeritus of Geography and INSTAAR Fellow Emeritus, passed away in Boulder on June 6. Mark led Niwot LTER at CU for two program cycles, 2004-2014, and is responsible for many of the accomplishments and directions that continue on in our program. Mark also was a founder of the Critical Zone Observatory program at CU Boulder. Among his multiple awards, he was a Fulbright Scholar and appointed Fellow of the American Geophysical Union. 

As an academic scholar, Mark’s focus was on factors influencing the hydrology and biogeochemistry of watersheds, particularly high elevation ecosystems. He also was concerned about environmental impacts to watersheds throughout Colorado and the West. That focus led Mark to pursue several areas of environmental concern: 

Mark focused on nitrogen pollution from anthropogenic sources, being one of the first to recognize thresholds in nitrogen inputs to landscapes that alter the way nitrogen cycles through the ecosystem and could cause large deleterious changes in ecosystems often downstream from the source of pollution and inputs to the watershed. His findings spurred studies that are still ongoing today. 

Mark and his students and colleagues recognized that greater understanding of the water quality impacts of acid rock drainage throughout the Colorado Mineral Belt required knowledge of groundwater flow paths and mineral weathering rates. His work set the stage for remediation efforts in several critical watersheds in southwestern Colorado. 

Mark recognized that energy extraction methods had very large consequences on groundwater, and he contributed to a state-of-the-art assessment of fracking as a means of oil and gas extraction in the Great plans. 

Perhaps most significantly, Mark saw the early signs of climate change affecting our mountains. Beginning in the 1990s, Mark and his students worked on a series of projects at NWT that monitored snowpack and the consequences of snow amounts and seasonality, and the consequences of early snowmelt. He demonstrated that snow functioned in multiple ways above and beyond its role as water provider to the west. He argued that our mountains are the water towers of the West, and that snow was the timing factor affecting the availability of that water. His snow survey program for the Front Range in the Green Lakes Valley of the Front Range is something we still conduct.

Mark has left a legacy of colleagues through his sponsorship of 35 graduate students and four postdocs, and his participation in multiple interdisciplinary studies. His legacy has allowed for so many successes at Niwot Ridge LTER. We honor his lasting impacts to our program and celebrate all his accomplishments. We will plan a time when we can come together and honor his contributions to NWT and high elevation science, likely this summer or fall.