Report: Wyoming cloud seeding program said to increase snowpack


Click here to read the draft executive summary. Here’s an excerpt:

The Wyoming Weather Modification Pilot Program (WWMPP) was conducted to assess the feasibility of increasing Wyoming water supplies through winter orographic cloud seeding. Following a Level II feasibility study that found considerable potential for cloud seeding in the state (WMI 2005), the Wyoming Water Development Commission (WWDC) funded the WWMPP (2005-2014) as a research project to determine whether seeding in Wyoming is a viable technology to augment existing water supplies, and if so, by how much, and at what cost. The WWMPP then established orographic cloud- seeding research programs in three Wyoming mountain ranges considered to have significant potential: the Medicine Bow, Sierra Madre, and Wind River Ranges…

Orographic cloud seeding is a technology designed to enhance precipitation in winter storms with an inefficient precipitation process due to a lack of natural ice nuclei. This inefficiency allows supercooled water to persist for long periods instead of being depleted by ice crystals, which grow and fall as snow. This fact is well documented by the measurement of sustained supercooled liquid water in orographic clouds taken by aircraft and ground-based instruments, such as radiometers. In contrast to natural ice nuclei, artificial ice nuclei, such as silver iodide, will nucleate substantial numbers of ice crystals at subfreezing temperatures of −8 °C (+17 °F) and cooler, creating ice crystals in clouds that are typically too warm for natural ice formation. In the presence of supercooled water droplets, these ice crystals rapidly grow into larger particles that fall to the ground as snow. The technology of orographic cloud seeding uses ground-based generators to produce a silver iodide plume, which is then transported by the ambient wind into orographic clouds to increase precipitation. This process of seeding clouds to create additional snow is complex and to date has not been scientifically verified in well-designed statistical tests.

More cloud seeding coverage here.

How scientists unraveled the El Nino mystery — Climate Central

El Niño (ENSO) phenomenon graphic from the Climate Predication Center via Climate Central
El Niño (ENSO) phenomenon graphic from the Climate Predication Center via Climate Central

Hermosa Creek in southwest Colorado gains protection — The Denver Post

From The Denver Post (Mark Matthews):

In a win for both conservationists and snowmobile riders, more than 100,000 acres of wilderness in southwest Colorado soon will gain an extra layer of protection under legislation that passed the U.S. Senate on Friday.

The safeguards for the Hermosa Creek area, near Durango, were included as part of a broad defense bill that sailed through the Senate by an 89-11 vote. The measure now heads to President Barack Obama, who is expected to sign it.

“The cooperation, compromise and hard work put into this bill over a number of years by a diverse group of Coloradans should serve as a model for Washington,” U.S. Sen. Michael Bennet, D-Colo., said in a statement.

Its passage caps the end of a legislative journey begun years ago when community leaders near Durango began debating how best to protect the Hermosa Creek area while allowing its use by backpackers, anglers and snowmobile riders.

That debate led to a compromise land-use proposal that became the basis of federal legislation introduced last year by Bennet and fellow lawmakers U.S. Sen. Mark Udall, D-Colo., and U.S. Rep. Scott Tipton, R-Cortez.

Its prospects of becoming law looked good until September, when Tipton sought to amend the legislation as it moved through the House. Broadly, the changes he supported would have “locked in” snowmobile trails in the Molas Pass area of Hermosa Creek while raising the possibility of widespread mining throughout the region.

Tipton said he backed the revisions to help local business. But the eleventh-hour changes threatened to sink the legislation, as they came only a few weeks before lawmakers were to conclude their business for the 113th session of Congress.

The move triggered another round of negotiation between Bennet and Tipton, who ultimately agreed to new language that restricted mining in nearly all of the new preserve while providing a small amount of flexibility in the routing of snowmobile trails.

“The people of southwest Colorado who have dedicated so much time and effort as a community to help craft and support this legislation that will protect the Hermosa Creek Watershed and the multiple uses of that land have reason to celebrate today,” Tipton said in a statement.

An aide to Bennet said the legislation would take effect as soon as Obama signs the bill.

As written, it sets aside about 38,000 acres in the Hermosa Creek watershed as wilderness — a designation that prohibits roads, mining and mechanized vehicles — and transforms another 70,650 acres into a “special management area” that would support activities from ATV riding to “selective timber harvesting,” according to a synopsis of the bill.

Mining would be allowed on roughly 2,400 acres of the new preserve.

Here’s the release from Conservation Colorado:

Conservation Colorado Wilderness Advocate, Scott Braden, released the following statement on Congress passing the Hermosa Creek Watershed Protection Act, attached to the National Defense Authorization Act, which now heads to President Obama’s desk to be signed into law:

“Today is an historic and celebratory day for Colorado. Thanks to the diligent work of U.S. Senator Michael Bennet, U.S. Representative Scott Tipton, and local stakeholders in southwest Colorado, we are poised to add 108,000 acres of protected lands, including 37,236 acres of new wilderness, to the Hermosa Creek Watershed near Durango. This stunning area will now be protected to continue providing vital wildlife habitat, unparalleled recreation opportunities, and clean water for the region for generations to come.

Conservation Colorado has partnered with a wide array of diverse stakeholders in southwestern Colorado to promote protections for Hermosa Creek, and today those efforts, and the efforts of so many of our partners and friends, have paid off. It is refreshing to see Congress acting in bipartisan fashion to protect public lands that are crucial to our local economy, environment, and our quality of life. While not every public lands portion of the National Defense Authorization Act is a win for the environment, designating 250,000 acres of new wilderness across the country breaks a long drought in Congressional land protection. We sincerely thank Rep. Tipton and Sen. Bennet, for honoring the community consensus spirit of the Hermosa Creek effort and protecting an important part of Southwest Colorado for current and future generations to enjoy.”

More Hermosa Creek coverage here and here.

Snowpack news: Flat-line, but there is hope

Click on a thumbnail graphic for a gallery of snowpack data from the Natural Resources Conservation Service.

From the Glenwood Springs Post Independent (John Stroud):

El Niño-influenced weather patterns that have brought much-needed rains to drought-stricken Southern California have also left Colorado ski resorts high and dry heading into the critical holiday season after a spate of early snowstorms allowed many ski areas to open ahead of schedule.

The culprit, according to Joe Ramey, a forecaster and climate specialist with the National Weather Service in Grand Junction, is the warmer-than-normal sea temperatures in the eastern Pacific Ocean that define El Niño years.

“Through November, we had storms coming in from the Pacific Northwest, plowing in across Seattle and the northern Rockies and grazing northern Colorado,” Ramey explained. “But that pattern has broken down now.”

In its place is a more typical El Niño pattern where storms are now tracking due east off the Pacific and across Southern California and the desert Southwest.

“That tends to leave the central mountains and northwest Colorado drier than normal,” Ramey said.

That’s not to say the same pattern will dictate the entire winter season, but it has been the trend in other El Niño years, most recently 2009-10 and 2006-07, he said.

Conversely, years when eastern Pacific sea temperatures are colder, known as La Niña, tend to produce more snow in the central and northern Rockies, while neutral years, such as the past two winters, “tend to be wild card years,” Ramey said.

At any rate, a lack of new snow since Nov. 26 and forecasts calling for daytime highs in the mid- to upper 40s this week with little chance of precipitation until next weekend prompted Sunlight Mountain Resort south of Glenwood Springs to suspend lift operations until Friday.