Mercury's surface in "enhanced color," a color scheme created to emphasize color differences. This is not what Mercury would look like to the human eye, but by applying mathematical analysis to images, color differences can be accentuated beyond those visible to a person.
Mount Rushmore National Memorial under construction.
The workers had to endure conditions that varied from blazing hot to bitterly cold and windy. Each day they climbed 700 stairs to the top of the mountain to punch-in on the time clock. Then 3/8 inch thick steel cables lowered them over the front of the 500-foot face of the mountain in a "bosun chair." Despite the dangers, no one was killed during the project.
Otters in Glacier Bay National Park and Preserve, Alaska.
The sea otter population of Glacier Bay has increased dramatically in the past 20 years. Ecologists consider sea otters a keystone species here. Otters consume vast quantities of clams, urchins, crabs, and other invertebrates and their presence creates ripples through the ecosystem. NPS photo.
Every day someone like you becomes a wildland wildfire fighter, a teacher, a trail-builder, a museum curator, or a park ranger. Discover your opportunities in national parks. Come to play. Come to learn. Come to serve. Develop your environmental leadership skills. Find a job. Be the next generation to preserve and protect these great places.
With more than 80% of Americans living in urban areas, urban parks are more important than ever. The father of American landscape architecture, Frederick Law Olmsted, said of urban parks:
It is one great purpose of the Park to supply to the hundreds of thousands of tired workers, who have no opportunity to spend their summers in the country, a specimen of God's handiwork that shall be to them, inexpensively, what a month or two in the White Mountains or the Adirondacks is, at great cost, to those in easier circumstances.
Salazar Announces Improvements to Glen Canyon Dam Operations to Restore High Flows and Native Fish in Grand Canyon
Adaptive management strategy meets water and power supply needs
WASHINGTON – Secretary of the Interior Ken Salazar announced today that, as part of the Interior's Glen Canyon Dam Adaptive Management Program, and in cooperation with five Interior agencies, the Bureau of Reclamation is approving two long-term research and experimental programs of high-flow releases and native fish protection to preserve and improve the Grand Canyon and its resources. Together, these decisions represent the most important experimental modification of operations of Arizona's Glen Canyon Dam in over sixteen years.
The two programs authorize changes in flow releases from the dam to meet water and power needs, but also to allow better conservation of sediment downstream, more targeted efforts to control non-native fish predation, and continued scientific experimentation, data collection, and monitoring to better address the important resources in the Colorado River below Glen Canyon Dam.
“We've gained tremendous knowledge about the unique resources of the Grand Canyon in the Colorado River downstream of Glen Canyon Dam over the past sixteen years,” said Secretary Salazar. “Today's decisions constitute a milestone in the history of the Colorado River and will provide a scientific foundation to improve future operations to benefit resources in the Grand Canyon, as well as the millions of Americans who rely on the river for water and power.”
The first program establishes a long-term protocol for testing high-flow releases from Glen Canyon dam to determine whether multiple high flow events can be used to rebuild and conserve sandbars, beaches, and associated backwater habitats that have been destroyed or lost over the years of the dam's construction and operation. The experimental protocol will simulate natural flood conditions in order to provide key wildlife habitat, potentially reduce erosion of archaeological sites, enhance riparian vegetation, maintain or increase camping opportunities, and improve the wilderness experience along the Colorado River in Grand Canyon National Park. The protocol is designed to take full advantage of sediment provided by tributaries of the Colorado River as a result of rainstorms and monsoons.
The protocol for high-flow experimental releases applies scientific information gained in previous high flow releases in 1996, 2004, and 2008 and provides the necessary, flexible framework to conduct further experimental releases through 2020 to determine the optimal timing, duration, frequency, and conditions that will maximize ecological and riparian benefits downstream in the Grand Canyon. For more information on the program, click here.
The second program outlines a series of actions and research to control non-native fish and protect endangered native fish in the Colorado River below Glen Canyon Dam. Conservation of native fish, particularly the endangered humpback chub, will be enhanced by reducing the threat of predation and competition from non-native fish and improving critical habitat. The actions will also ensure continued compliance with the Endangered Species Act and a Final Biological Opinion issued by the U.S. Fish and Wildlife Service in 2011. Extensive government-to-government tribal consultations and analyses were conducted to ensure the required non-native fish control actions can be implemented in a way that respects tribal perspectives. For more information on the program, click here.
“Implementation of these two programs marks a huge step forward in integrating the management of a dam that's critical to the delivery of water and power to millions of people in the Southwest with better conservation of the incredible values of the Grand Canyon,” said Assistant Secretary for Water and Science Anne Castle. “We are refining our operations to reflect what we've learned and address the concerns expressed by several Native American tribes about the management of fish at locations honored as sacred sites by many of the tribes and pueblos.”
The actions outlined in both detailed Environmental Assessments completed today include important scientific research and monitoring components that are fundamental to the adaptive management process. Reclamation has primary responsibility for operation of Glen Canyon Dam and the National Park Service has primary responsibility for Grand Canyon National Park and Glen Canyon National Recreation Area.
"The National Park Service is a strong supporter of high flow tests to help determine how best to rebuild and sustain the beaches and sand bars below Glen Canyon Dam. We appreciate the extensive collaboration required to develop these research programs which are critical to preserving the awesome resources and visitor experience along the Colorado River in Grand Canyon National Park," said Jonathan B. Jarvis, Director of the National Park Service.
Today's actions represent the most comprehensive experiment for protection of the Grand Canyon since Secretary of the Interior Bruce Babbitt signed a Record of Decision in 1996 and conducted the first high flow release. The experiments will help answer critical questions about the complex interactions between dam releases and resource responses, and also advance the goal of the Grand Canyon Protection Act to improve resource conditions.