The stark, breathtaking beauty of the high desert is immediately apparent in Sky Island, a profile of the landscape and ecosystem of the Jemez Mountains, a volcanic range in northern New Mexico. But there is deception at work here: behind the beauty lies a natural disaster, slow-moving but inexorable.

"When I started making natural history films 20 years ago, 'global warming' had hardly entered the lexicon," says environmental filmmaker John Grabowska. "Now I can't imagine making a film that doesn't somehow address climate change and its impacts. It is the most consequential issue of our time."

Sky Island, which Grabowska wrote, produced and directed, will air nationally on PBS as a prime time special Sunday, July 10, 2011. The film takes audiences on a journey through the desert and alpine ecosystem from the canyon floor of the Rio Grande to the peaks of the Jemez, examining the life zones that change dramatically along with the increase in elevation.

The title of the film comes from a phenomenon common in the Desert Southwest: isolated mountains that rise up from the desert floor, with unique populations of plants and animals that have evolved on the mountaintops and cannot migrate elsewhere because of the desert that surrounds them.

"The collected peaks of the Jemez were akin to the individual sky island mountains, but on a massive scale," Grabowska explains. "They harbor a surprising degree of diversity and really are like islands of  life surrounded by a desert sea. The Jemez are the epicenter of climate change in the Desert Southwest. Outside of the polar regions, some of the most visible and rapid changes are seen in high altitudes, particularly in arid lands. That describes the Jemez.

"Seen from space, the mountains are a near-perfect circle," Grabowska continues. "There is a smaller circle at the center that is actually a huge valley, the caldera of a giant volcano that erupted just over a million years ago and then collapsed. Most of the mountains and surrounding plateaus are protected land, managed by the Santa Fe National Forest and Bandelier National Monument.

"The Jemez have been sacred to several Pueblo tribes for generations," Grabowska points out, "and substantial portions of  land are owned by the Pueblos. San Ildefonso and Santa Clara Pueblos lie right on the flanks of the mountain. The Pueblo people still revere the land and care deeply about how it is treated."

The film's spare, poetic script is narrated by Meryl Streep and N. Scott Momaday, a scholar, author and poet who was the first Native American to win a Pulitzer Prize for literature. He spent his formative childhood years in the Jemez Mountain area and until recently had a home there.

The structure of the film reflects that of the mountain itself, starting at the Rio Grande bottomlands and journeying to the top. Grabowska says the idea came from early scientific research done in the Desert Southwest by C. Hart Merriam, a biologist and co-founder of  The National Geographic Society.

"Merriam noticed that going uphill on a desert mountain was similar to traveling north to arctic latitudes," notes Grabowska. "Increase in elevation brings increased moisture and lower temperatures, not unlike going from Mexico to Canada. At the base of the mountain we see desert steppe with grass and scrub oak. As we ascend, the flora and fauna change, first to pinyon-juniper scrub, then Ponderosa pine, and finally to alpine forest."

Grabowska says that several sequences narrated by Momaday were inspired by his own writings.

 "Scott Momaday provides lyrical and meditative insights into certain sequences and locations, often adaptations of his own writings. He brings a wisdom and sensitivity regarding this particular place that perhaps no one else can. He's sometimes described as the voice of the Southwest, and he is that for me. I was impressed with how willing he was to reflect in the film on his mortality and, by extension, our own."

Mortality is not limited to humankind in the film. During a two-year period of  heat and drought, the pinyon pine forest, an icon of the region, collapsed. "Ninety percent of the pinyon on the Pajarito Plateau just died, stressed out from the heat and drought, no longer able to resist pine beetle infestations," says Grabowska. "Where we once saw these salmon-colored landscapes dotted with green, we now see gray, dead pinions--at least until they collapse into a pile of  bleached wood. The Desert Southwest is getting hotter and dryer and it is easily, and sadly, visible."

Many animal species on the mountaintops are marooned on this desert island. The film highlights an endemic salamander and the southernmost population of American pikas, small rabbit-like mammals that depend on cool temperatures to survive. Pikas die after a few hours of exposure to temperatures above 78ºF.

"Meryl narrates a part in the script about how climate change will determine which forms of life will survive--and how," Grabowska says. "Some species in the Jemez Mountains have nowhere else to go. They can't migrate, and they can't move any further uphill because they're already at the top."

Grabowska began his career as a television news reporter and cameraman. He was a Peace Corps volunteer in Central America and worked on legislation on Capitol Hill. His previous natural history films for PBS include Ribbon of Sand, which focuses on a wild, undeveloped stretch of barrier islands off the North Carolina coast; Yellowstone: Land to Life, which takes audiences on a journey through the national park; Remembered Earth, which examines portions of the Colorado Plateau; and Crown of the Continent, which The Washington Post described as "both a spectacular testament to the architectonics of the planet itself, and a surprisingly intimate and moving tribute to his own father's dreams."

Grabowska began production on Sky Island in 2005, working with his long-time collaborator, cinematographer Steve Ruth, to gather images in Super 16 film format. "The organic look of film suits the subject matter, with wide open landscapes and the wilderness ecosystem," Grabowska maintains. "Cinematographers' eyes just light up when I say I'm shooting on film."

Grabowska had specific ideas about what he wanted to get on film, but production was mainly a process of time-intensive discovery that began with hiking and driving through the area. Ruth carried an Aaton XTR Prod camera with Zeiss prime and Angenieux 11.5:138 mm zoom lenses. He had Kodak Vision 2 7201 50 D color negative film on his palette.

There was no way to control lighting other than waiting and finding the right angles. "The latitude of the stock helped a lot in high contrast situations, and there are quite a few of those in the desert," Grabowska observes.

About halfway through the project, Ruth had to leave because of an illness in his family. Grabowska found freelance cinematographers in the region to complete shooting the film.

"These are the mountains where the 2000 Cerro Grande fire burned out of control, but fire is integral to the health of the natural landscape," Grabowska explains. "Profiling this ecosystem without including a fire would be anathema. I had counted on Steve to shoot a prescribed fire for me. The land managers don't schedule burns according to film production schedules. They wait for the right conditions. I needed a cinematographer who would be ready to shoot at a moment's notice."

In 2008, a prescribed fire was set to reduce the amount of duff and brush on the forest floor in Bandelier National Monument to avoid future catastrophic fires. Grabowska contacted Dyanna Taylor, a cinematographer who lives in the Santa Fe area. He knew her by reputation and through friends in the industry. Her grandmother, Dorothea Lange, was an iconic photo-journalist whose pictures documented the story of the Great Depression during the 1930s. Taylor learned the art of telling stories with pictures while watching her grandmother make prints in her darkroom.

"I love the fire and ice sequence Dyanna filmed," Grabowska notes. "Fire is so visually dynamic anyway, but Dyanna really understands its importance in the ecosystem, which really comes through in her images. Since she lives nearby she was also able to shoot scenics right after a snowfall, which doesn't last long down in the desert canyons. I put the two sequences together, fire followed by ice, and Todd Boekelheide's music is simply transcendent."

Academy Award-winner Boekelheide, another of Grabowska's long-time collaborators, created and recorded an original music score at Fantasy Studios in Berkeley, CA.

John Britt, whose footage included the extensive aerials, also stepped in after Ruth's departure. Additional cinematography was by Scott Ransom and Michael Male.

Other members of his crew included Grabowska's teenaged daughters Hilary and Sierra, who recorded sound, hauled gear and shot production stills.

The negative was processed at Colorlab and NFL Films. Bobby Johanson and Jim Coyne at NFL Films transferred the film to digital HD format. Dave Markun at Henninger Media did the color correction after the final cut was done by Matt Witkowski in HDCAM-SR format.

Bob Fisher has been writing about cinematography and film preservation for over 30 years.