The United States Geological Service is modeling the effects of climate change on various basins around the U.S. Here’s a release from the agency (Kara Capelli):

“We are unlikely to see a ‘water-as-usual’ future.” – Marcia McNutt, USGS Director

Arguably, the most important impacts of climate change – including those to ecosystems, agriculture, energy, and industry – will be tied to changes in water availability, especially as the world becomes increasingly water-stressed. It’s crucial that water managers understand the likely impacts of climate change, so that they can plan for new conditions and challenges.

How will your water be affected?

Understanding the impacts that climate change will have on water availability in specific regions and communities is a mammoth task. Water availability in every region, basin, and watershed will be affected differently, depending on the specific precipitation and hydrologic conditions in that area.

Also, for all of the models and technology we have available at our 21st century finger tips, weather patterns are still notoriously unpredictable. Forecasting future precipitation conditions is even more difficult, especially under new climate scenarios, and changes to weather patterns will vary across the country.

Complicating water availability predictions further, each basin has its own unique set of hydrologic and geologic features that affect how much water is available, where that water comes from, and how it flows through a system.

Little by little, though, scientists are beginning to build the information and tools to understand the nuanced effects of climate change to the Nation’s water resources.

USGS predicting changes to water availability in 14 basins across the Nation

In a first-of-its-kind study, scientists from the USGS have predicted changes to water resources for 14 different basins across the country.

First, the scientists downscaled vast climate models, in order to understand changes in temperature and precipitation specific to the 14 study basins. They then used USGS hydrologic models and streamgage information to project how water resources will be impacted by the changing weather patterns, taking into account specific hydrologic and geologic features in each basin, such as snowpack, drought, and groundwater conditions.

For example, the USGS models project that changes to snowpack in the Sprague River Basin in Oregon could cause annual peak streamflows to occur earlier in the spring as overall basin storage decreases. This means that managers may be forced to modify storage operation and reprioritize water delivery for environmental and human needs.

In many areas the biggest impacts to water resources will be a factor of reduced snowpack. For example snowpack in the headwaters of the Colorado River could affect the amount and timing of streamflow to the Colorado River and also impact important recreation areas.

Portions of Maine may see higher streamflows, which could affect populations of endangered Atlantic salmon. On the other hand, areas of the already drought-stressed Flint River Basin, one of Atlanta’s primary drinking water supplies, are projected to become even drier.

More USGS coverage here.

Here’s a nice concise history of the USGS (Mary C. Rabbitt). Click through for the whole series of articles, cool drawings and photographs. Here’s the announcement:

The United States Geological Survey was established on March 3, 1879, just a few hours before the mandatory close of the final session of the 45th Congress, when President Rutherford B. Hayes signed the bill appropriating money for sundry civil expenses of the Federal Government for the fiscal year beginning July 1, 1879. The sundry civil expenses bill included a brief section establishing a new agency, the United States Geological Survey, placing it in the Department of the Interior, and charging it with a unique combination of responsibilities: “classification of the public lands, and examination of the geological structure, mineral resources, and products of the national domain.” The legislation stemmed from a report of the National Academy of Sciences, which in June 1878 had been asked by Congress to provide a plan for surveying the Territories of the United States that would secure the best possible results at the least possible cost. Its roots, however, went far back into the Nation’s history.

The first duty enjoined upon the Geological Survey by the Congress, the classification of the public lands, originated in the Land Ordinance of 1785. The original public lands were the lands west of the Allegheny Mountains claimed by some of the colonies, which became a source of contention in writing the Articles of Confederation until 1781 when the States agreed to cede their western lands to Congress. The extent of the public lands was enormously increased by the Louisiana Purchase in 1803 and later territorial acquisitions.

At the beginning of Confederation, the decision was made not to hold the public lands as a capital asset, but to dispose of them for revenue and to encourage settlement. The Land Ordinance of 1785 provided the method of surveying and a plan for disposal of the lands, but also reserved “one-third part of all gold, silver, lead, and copper mines to be sold or otherwise disposed of, as Congress shall thereafter direct,” thus implicitly requiring classification of the lands into mineral and nonmineral. Mapping of the public lands was begun under the direction of the Surveyor-General, but no special provision was made for classification of the public lands, and it thus became the responsibility of the surveyor. There was,of course, no thought in 1785 or for many years thereafter of employing geologists to make the classification of the mineral lands, for geology was then only in its infancy.

More USGS coverage here.

From the Loveland Connection (Bobby Magill):

Using tree ring samples to reconstruct the size of mountain snowpack over the past millennium, USGS researchers were able to show that reductions in the size of the mountain snowpack across the West during the past 30 years is unusual when considering the size of the mountain snowpack each year during the past three centuries…

There was an “inflection point” in the 1980s when the size of a given year’s snowpack was more influenced by temperature than by amount of precipitation, said USGS research scientist Gregory Pederson, lead author of the study, “The Unusual Nature of Recent Snowpack Declines in the North American Cordillera.”[…]

“The region you are sitting in is a particularly dynamic one,” he said. “These basins haven’t shown the substantial temperature-driven declines since the 1980s. (Colorado’s northern mountains) seem fairly resistant to fairly extensive snowpack decline like you see across the Northern Rockies.”

Here’s the release from the United States Geological Survey:

A USGS study released today suggests that snowpack declines in the Rocky Mountains over the last 30 years are unusual compared to the past few centuries. Prior studies by the USGS and other institutions attribute the decline to unusual springtime warming, more precipitation falling now as rain rather than snow and earlier snowmelt.

The warming and snowpack decline are projected to worsen through the 21st century, foreshadowing a strain on water supplies. Runoff from winter snowpack – layers of snow that accumulate at high altitude – accounts for 60 to 80 percent of the annual water supply for more than 70 million people living in the western United States.

“This scientific work is critical to understanding how climate change is affecting western water supplies,” Secretary of the Interior Ken Salazar said. “It helps land managers adapt to changing conditions on the ground, assists water managers with planning for the future, and gives all of us a better understanding of the real impacts that carbon pollution is having on our resources and our way of life.”

USGS scientists, with partners at the Universities of Arizona, Washington, Wyoming, and Western Ontario, led the study that evaluated the recent declines using snowpack reconstructions from 66 tree-ring chronologies, looking back 500 to more than 1,000 years. The network of sites was chosen strategically to characterize the range of natural snowpack variability over the long term, and from north to south in the Rocky Mountains.

With a few exceptions (the mid-14th and early 15th centuries), the snowpack reconstructions show that the northern Rocky Mountains experience large snowpacks when the southern Rockies experience meager ones, and vice versa. Since the 1980s, however, there were simultaneous declines along the entire length of the Rocky Mountains, and unusually severe declines in the north.

“Over most of the 20th century, and especially since the 1980s, the northern Rockies have borne the brunt of the snowpack losses,” said USGS scientist Gregory Pederson, the lead author of the study. “Most of the land and snow in the northern Rockies sits at lower and warmer elevations than the southern Rockies, making the snowpack more sensitive to seemingly small increases in temperature. Also, winter storm tracks were displaced to the south in the early 20th century and post-1980s. Forest fires were larger, more frequent and harder to fight, while Glacier National Park lost 125 of its 150 glaciers.”

USGS scientist and co-author Julio Betancourt explains that “The difference in snowpack along the north and south changed in the 1980s, as the unprecedented warming in the springtime began to overwhelm the precipitation effect, causing snowpack to decline simultaneously in the north and south. Throughout the West, springtime tends to be warmer during El Niño than La Niña years, but the warming prior to the 1980s was usually not enough to offset the strong influence of precipitation on snowpack.”
The La Niña episode this year is an example with lots of snow in the north while severe drought afflicts the south. But, in the north, this year’s gains are only a small blip on a century-long snowpack decline.

In the West, the average position of the winter storm tracks tend to fluctuate north and south around a latitudinal line connecting Denver, Salt Lake City and Sacramento. In El Niño years, winter storms track south of that line, while in La Niña years, they track to the north.

This study supports research by others estimating that between 30-60 percent of the declines in the late 20th century are likely due to greenhouse gas emissions. The remaining part of the trend can be attributed to natural decadal variability in the ocean and atmosphere, which is making springtime temperatures that much warmer.

“What we have seen in the last few decades may signal a fundamental shift from precipitation to temperature as the dominant influence on western snowpack.” Pederson said.

The study, The unusual nature of recent snowpack declines in the North American Cordillera, is online at Science magazine http://www.sciencemag.org/lookup/doi/10.1126/science.1201570.

More coverage from Chris Woodka writing for The Pueblo Chieftain. From the article:

USGS scientists, with partners at the universities of Arizona, Washington, Wyoming, and Western Ontario, led the study that evaluated the recent declines using snowpack reconstructions from 66 tree-ring chronologies, looking back 500-1,000 years. With a few exceptions (the mid-14th and early 15th centuries), snowpack reconstructions show that the northern Rocky Mountains experience large snowpacks when the southern Rockies experience meager ones, and vice versa. Since the 1980s, however, there were simultaneous declines along the entire length of the Rocky Mountains, and unusually severe declines in the north.

More coverage from Felicity Barringer writing for The New York Times weblog Green. From the post:

On the one hand, the underlying narrative was depressingly familiar, synchronizing with other studies or predictions involving California’s Sierra, the Himalayas and other spots around the world. What drew my attention is the reminder that snowmelt in the Rockies feeds three huge river systems — the Colorado, the Columbia and the Missouri — on which 70 million Americans depend for water.

Not that everyone living along — or flooded out of the communities along — the Missouri River or its swollen tributaries would consider these findings intuitive. But the U.S.G.S. scientists who led the study point out that climate in the Rocky Mountains has for centuries been an either-or proposition.

It works like this. Draw a hypothetical line in your mind from Denver to Salt Lake City to Sacramento. If there is heavy snow to the north of this line, chances are there will be a drought to the south of it. And vice versa. Or, as an Interior Department press release said, “With a few exceptions (the mid-14th and early 15th centuries), the snowpack reconstructions show that the northern Rocky Mountains experience large snowpacks when the southern Rockies experience meager ones, and vice versa.”

More coverage from United Press International. From the article:

The study backs research that the USGS said estimates that as much as 60 percent of the snowpack declines in the late 20th century are because of greenhouse gas emissions, which are linked to higher global temperature averages…Runoff from winter snowpack makes up nearly 60 percent of the annual water supply for people in the western United States.

More coverage from Craig Welch writing for The Seattle Times via the Bend Bulletin. From the article:

Pederson and his colleagues say the findings are important because they suggest the mountain snows that produce the runoff that powers the Columbia, the Missouri and the Colorado river systems will continue to decline as global temperatures rise, even if precipitation increases.

More coverage from Margaret Munro writing for The Vancouver Sun. From the article:

The study, published Thursday in the journal Science, says the changes are affecting the Colorado, Columbia and Missouri Rivers, which together supply water to 70 million Americans. And they are also altering river flows in the Canadian prairies and central British Columbia, said co-author Brian Luckman, at the University of Western Ontario.

“Snowpack is essential for water supply to many of these areas,” Luckman said, noting that the Rockies feed rivers flowing through central B.C. and the Bow, Athabasca and Oldman rivers in Alberta. “Between 60 to 80 per cent of the water in those rivers is snowmelt from the mountains.”

Mountain snow records don’t go back far beyond 1950, so the team, led by Gregory Pederson at the U.S. Geological Survey, looked at tree rings at 66 sites from B.C. to Colorado to get a read on snowpack levels over the past 800 years.

They found that the snowpack shrank more during the late 20th century than during any other period since 1200 AD, with more severe declines at the northern end of the range studied.

Luckman says the tree rings track the depth of the snowpack because some species such as the alpine larch tend not to grow well in heavy snowpack years because it takes so long for water to start flowing on mountaintops. Trees like Ponderosa Pines at lower elevations thrive in years of heavy snowpack, resulting in thicker tree rings.

More coverage from Joey Bunch writing for The Denver Post. From the article:

The dire long-term forecast cites warmer springs, earlier snowmelts and shifting winter storm patterns, all possible byproducts of global warming caused by greenhouse-gas emissions, according to the USGS. While that could prove disastrous for Colorado’s ski and rafting industries, it’s too early to say if it means less water overall, said Marc Waage, the manager of water-resources planning for Denver Water, which supplies 1.3 million people in the metro region. “I don’t think from this study you can conclude that the overall amount of water is going to decline,” he said, “because we could be compensating snowpack with rain.”

More USGS coverage here.

I’ve been watching Clear Creek at Golden and the Cache la Poudre at Fort Collins via the text message service, USGS Water Alert. You choose a threshold for either gage height or flow in cubic feet per second along with a frequency for notification. Notification is via text message or email.

The USGS also runs an online application Water Watch. If you select by state, say Colorado, you can mouse over your favorite gage and read the current stats. The application shows a graphical representation of all reporting gages across the state as well.

Click on the thumbnail graphic above and to the right for a screen shot from this morning. The dots represent current streamflow as compared to average at the location. The legend is at the bottom.

Update: The state website is now back up.

The state’s website is not responding this morning so I’ll point you to it when the link will work.

Wow, Flood DSS is also down. That can’t be good if you’re depending on it for information to use for flood response or emergency response this weekend.

The outage is widespread. The governor’s and state legislature’s websites are not reachable .

Here’s the link to the report here’s the release from the USGS (Daren Carlisle/Kara Capelli):

The amount of water flowing in streams and rivers has been significantly altered in nearly 90 percent of waters that were assessed in a new nationwide USGS study. Flow alterations are a primary contributor to degraded river ecosystems and loss of native species.

“This USGS assessment provides the most geographically extensive analysis to date of stream flow alteration,” said Bill Werkheiser, USGS Associate Director for Water. “Findings show the pervasiveness of stream flow alteration resulting from land and water management, the significant impact of altered stream flow on aquatic organisms, and the importance of considering this factor for sustaining and restoring the health of the Nation’s streams and ecosystems.”

Flows are altered by a variety of land- and water-management activities, including reservoirs, diversions, subsurface tile drains, groundwater withdrawals, wastewater inputs, and impervious surfaces, such as parking lots, sidewalks and roads.

“Altered river flows lead to the loss of native fish and invertebrate species whose survival and reproduction are tightly linked to specific flow conditions,” said Daren Carlisle, USGS ecologist and lead scientist on this study. “These consequences can also affect water quality, recreational opportunities and the maintenance of sport fish populations.”

For example, in streams with severely diminished flow, native trout, a popular sport fish that requires fast-flowing streams with gravel bottoms, are replaced by less desirable non-native species, such as carp. Overall, the USGS study indicated that streams with diminished flow contained aquatic communities that prefer slow moving currents more characteristic of lake or pond habitats.

“Management practices related to water demand continue to alter stream flows in many places,” said Jeff Ostermiller, Water Quality Manager with the Utah Division of Water Quality. “Understanding the ecological effects of these flow alterations helps water managers develop effective strategies to ensure that water remains sufficiently clean and abundant to support fisheries and recreation opportunities, while simultaneously supporting economic development.”

Annual and seasonal cycles of water flows — particularly the low and high flows — shape ecological processes in rivers and streams. An adequate minimum flow is important to maintain suitable water conditions and habitat for fish and other aquatic life. High flows are important because they replenish floodplains and flush out accumulated sediment that can degrade habitat.

“While this study provided the first, national assessment of flow alteration, focused studies within specific geographic regions will provide a better understanding of the ecological effects of altered stream flows, which can be more effectively applied to local water management challenges,” said Carlisle.

The severity and type of stream flow alteration varies among regions, due to natural landscape features, land practices, degree of development, and water demand. Differences are especially large between arid and wet climates. In wet climates, watershed management is often focused on flood control, which can result in lower maximum flows and higher minimum flows. Extremely low flows are the greatest concern in arid climates, in large part due to groundwater withdrawals and high water use for irrigation.

The study identified over 1,000 unimpaired streams to use as reference points to create stream flow models. The models were applied to estimate expected flows for 2,888 additional streams where the USGS had flow monitoring gauges from 1980-2007. The estimated values for the 2,888 streams were compared to actual, measured flows to determine the degree to which streams have been altered.

This study was conducted by the USGS National Water-Quality Assessment Program, which has assessed the physical, chemical and biological characteristics of streams and rivers across the nation since 1991.

For more than 125 years, the USGS has served as the Nation’s water monitoring agency, including flow and quality in selected streams and rivers across the United States. USGS continues to work closely with the Environmental Protection Agency and other federal agencies, states and local watersheds to assure that USGS monitoring and assessments provide useful information for managing and protecting streams throughout the Nation.

Water-quality data from more than 1,300 locations, much of it in real-time, are available through USGS Water Quality Watch. Additional information about surface water, groundwater and water quality is available at the National Water Information System Web Interface. You can also receive instant, customized updates about water conditions by subscribing to WaterAlert.

More coverage from The Summit County Citizens Voice (Bob Berwyn):

Flows are altered by a variety of land- and water-management activities, including reservoirs, diversions, subsurface tile drains, groundwater withdrawals, wastewater inputs, and impervious surfaces, such as parking lots, sidewalks and roads.

“Altered river flows lead to the loss of native fish and invertebrate species whose survival and reproduction are tightly linked to specific flow conditions,” said Daren Carlisle, USGS ecologist and lead scientist on this study. “These consequences can also affect water quality, recreational opportunities and the maintenance of sport fish populations.”

For example, in streams with severely diminished flow, native trout, a popular sport fish that requires fast-flowing streams with gravel bottoms, are replaced by less desirable non-native species, such as carp. Overall, the USGS study indicated that streams with diminished flow contained aquatic communities that prefer slow moving currents more characteristic of lake or pond habitats.

More USGS coverage here.



Click here for the USGS’ Water Watch website showing the map of real-time streamflow compared to historical streamflow. Click on the thumbnail graphic to the right for the Google map for tonight at 9:00 p.m.