#Water resources to become less predictable with #ClimateChange, declining #snowpack will cause more variability in runoff, streamflow — NCAR/UCAR

Declining snowpack will lead to more variable and unpredictable streamflow. Some of the snowmelt flowing in the Blue River as it joins the Colorado River near Kremmling, Colo., will reach the Lower Basin states. Dec. 3, 2019. Credit: Mitch Tobin, the Water Desk

Click the link to read the article on the NCAR/UCAR website (David Hosansky):

Water resources will fluctuate increasingly and become more and more difficult to predict in snow-dominated regions across the Northern Hemisphere by later this century, according to a comprehensive new climate change study led by the National Center for Atmospheric Research (NCAR).

The research team found that, even in regions that keep receiving about the same amount of precipitation, streamflow will become more variable and unpredictable. As snowpack recedes in a warmer future and fails to provide reliable runoff, the amount and timing of water resources will become increasingly reliant on periodic episodes of rain.

“Water managers will be at the whim of individual precipitation events instead of having four-to-six months lead time to anticipate snowmelt and runoff,” said NCAR scientist Will Wieder, the lead author. “Water management systems in snow-dominated regions are based on the predictability of snowpack and runoff, and much of that predictability could go away with climate change.”

Observations show that snowpack is already melting earlier, and even declining in many regions. This decline will become so pronounced toward the end of the century that the amount of water contained in snowpack at the end of an average winter in parts of the U.S. Rocky Mountains could plummet by nearly 80 percent, the scientists found.

The changes in runoff and streamflow are likely to have cascading impacts on ecosystems that depend on reliable water from snow, the study warns. Although the changes won’t be uniform across regions, more snow-free days and longer growing seasons will put stress on water resources, drying out soils in many areas and heightening fire risk.

The study assumes that emissions of greenhouse gasses continue at a high rate (a scenario known as SSP3-7.0). Wieder said that the most severe impacts on snowpack, runoff, and ecosystems would likely be avoided if society successfully reduced greenhouse gas emissions.

The scientists drew on an advanced set of computer simulations to fill in details about the future of water resources, showing the extent to which changes in temperature and precipitation will alter snow accumulation and runoff patterns in the Northern Hemisphere. Although past research looked at the impacts of climate change on water availability, the new study focuses on the increasing variability of water resources.

The study is being published the week of July 18 in the Proceedings of the National Academy of Sciences. It was funded by the U.S. National Science Foundation, which is NCAR’s sponsor.


Many regions of Earth rely on the accumulation of snow during the winter and subsequent melting in the spring and summer for regulating runoff and streamflow. For years, however, scientists have warned that the snowpack will become thinner and melt earlier as more precipitation during the colder months falls as rain instead of snow, and as melting occurs at times during the winter instead of the spring runoff season.

To determine how reduced snowpack will affect the variability of water resources, Wieder and his co-authors turned to a powerful NCAR-based climate model: the Community Earth System Model, version 2. They drew on a recently created database of simulations, known as the CESM2 Large Ensemble, to compare a past period (1940-1969) with a future period (2070-2099). The simulations were run on the Aleph supercomputer at the Institute for Basic Science supercomputer in Busan, South Korea.

The results illuminate the extent to which widespread shifts in the timing and extent of water flows will occur in much of the world by 2100. There will be an average of about 45 more snow-free days yearly in the Northern Hemisphere, assuming high greenhouse gas emissions. The largest increases will occur in midlatitudes that are relatively warm and high-latitude maritime regions that are influenced by changes in sea ice.

Many regions that rely the most on predictable relationships between snowpack and runoff will experience the largest loss in predictability because of a sharp decline in reliable pulses of spring runoff. These regions include the Rocky Mountains, Canadian Arctic, Eastern North America, and Eastern Europe. The authors warn that this will substantially complicate the management of freshwater resources, both for society and ecosystems.

“We are in a race with predictability when it comes to streamflow because we’re trying to improve our forecasts through better data, models, and physical understanding, but these efforts are being canceled by the rapid disappearance of our best predictor: snow,” said Flavio Lehner, a professor of earth and atmospheric science at Cornell University and a co-author of the study. “It might be a race we’ll lose, but we’re trying to win it, and that is why we need to study these topics.”

Although the reduced runoff will result in drier summertime soil conditions in much of the Northern Hemisphere, the simulations showed that certain regions — including East Asia, the Himalayas, and Northwestern North America — will maintain soil moisture because of increased rainfall.

“Snow-related metrics are critical for informing society’s management of precious water resources,” said Keith Musselman, a hydrologist at the University of Colorado Boulder and co-author of the study. “As utilities and civil works agencies plan new reservoirs and other infrastructure to adapt to a changing climate, we must address basic research questions about the changing characteristics of winter snowpack and resulting streamflow that we have long relied upon.”


Title: “Pervasive alterations to snow-dominated ecosystem functions under climate change

Authors: William R. Wieder, Daniel Kennedy, Flavio Lehner, Keith N. Musselman, Keith B. Rodgers, Nan Rosenbloom, Isla R. Simpson, Ryohei Yamaguchi
Journal: Proceedings of the National Academy of Sciences

The flight of the Nez Perce — USGS

Click the link to read the article on the USGS website:

Summer 2023 marks 146 years since the flight of the Nez Perce, when an indigenous tribe crossed Yellowstone in an attempt to reach Canada and during a running battle with the US army.

Yellowstone Caldera Chronicles is a weekly column written by scientists and collaborators of the Yellowstone Volcano Observatory. This week’s contribution is from Cole Messa, Ph.D. student and Professor Ken Sims, both in the Department of Geology and Geophysics at the University of Wyoming.

Throughout its history, Yellowstone has been frequented by numerous indigenous tribes. All of these groups have a unique and cherished tale bonding them with the land upon which Yellowstone sits, but perhaps one of the most harrowing and tragic recent stories is that of the Nez Perce (Nimiipu).

Photo of Hinmatóowyalahtq̓it (Chief Joseph) taken in November 1877 by O.S. Goff in Bismarck. From Wikipedia (https://commons.wikimedia.org/wiki/File:Chief_Joseph-1877.jpg).

In the summer of 1877, the gold rush and a series of treaty miscommunications resulted in the Nez Perce being driven from their homeland of the Wallowa Mountains in Oregon. A group of about 800 Nez Perce decided to refuse relocation to the newly established reservation, instead opting to seek a new home, led by their soft-spoken and stoic leader, Hinmatóowyalahtq̓it (also known as Chief Joseph). The voyage was meant to be peaceful, but skirmishes with settlers inevitably ensued, often times manifesting as back-and-forth revenge for killings committed during prior encounters. As a result, the Nez Perce’s trek to discover a new home, safe from the relentless encroachment of an ever-growing nation, became marked by fear and bloodshed.

After an initial skirmish in Idaho, the U.S. Army began to pursue the band of Nez Perce on their march east from the Wallowa Mountains, first making contact at White Bird Battlefield in western Idaho on June 17, 1877. While the U.S. Army was being greeted by a 6-person peace party of Nez Perce carrying a while flag, a civilian volunteer opened fire, sparking a battle which resulted in heavy casualties and ignited the flight of the Nez Perce toward Canada. The Nez Perce would continue to encounter the U.S. Army on numerous occasions during their journey, including at the Clearwater Battlefield (northeastern Idaho) and the Big Hole Battlefield (western Montana), before the group entered Yellowstone National Park on August 23, 1877.

Stinging from their loses at the 1876 Battle of Greasy Grass, or as it also known, the Battle of the Little Bighorn, and determined to punish the Nez Perce to discourage other indigenous tribes who might consider rebelling against the rule of the United States, the Nez Perce were pursued by over 2,000 U.S. Army soldiers. Yellowstone was not foreign country to the Nez Perce, who often visited the park in pursuit of its abundant resources and wild game. While within the park, the Nez Perce encountered 25 tourists, and looting of supplies and multiple revenge killings occurred. Today, you can follow the path of the Nez Perce through Yellowstone National Park along park roads near Nez Perce Creek, Otter Creek, Nez Perce Ford, and Indian Pond. The Nez Perce forded the Yellowstone River at Nez Perce Ford, traveled through Pelican Valley and Hoodoo Basin, and passed over the Absaroka Mountains, finally exiting Yellowstone National Park to head north towards the Canadian border, where they hoped to find safety. Before they could reach their destination, the Nez Perce were stopped by the U.S. Army once more in the foothills of the Bear’s Paw Mountains of northern Montana, only 40 miles away from Canada.

Route followed by a band of Nez Perce (or, in their language, Nimiipu or Nee-Me-Poo) in 1877. A band of 800 men, women, and children—plus almost 2,000 horses—left their homeland in what is now Oregon and Idaho pursued by the US Army. The group crossed through Yellowstone National Park in their attempt to reach Canada, and they were ultimately captured by US Army forces in northern Montana. Courtesy of the National park Service Yellowstone Spatial Analysis Center (https://www.nps.gov/yell/learn/historyculture/flightnezperce.htm).

This epic journey of the Nez Perce covered more than 1,170 miles across four states and multiple mountain ranges, and about 250 Nez Perce warriors held off the pursuing US Army troops in 18 battles, skirmishes, and engagements. Ultimately, hundreds of US soldiers and Nez Perce (including women and children) were killed in these conflicts before the Nez Perce surrendered, and Chief Joseph—one of the last surviving chiefs of the band—gave the now-famous speech* in which he said, “From where the sun now stands, I will fight no more forever.” Some of the Nez Perce were able to reach Canada, but the rest, including Chief Joseph, accepted resettlement in numerous reservations throughout the American northwest. Chief Joseph would pass away in 1904 at the age of 64 on the Colville Indian Reservation (WA) of a “broken heart”, per his doctor’s account. He is buried near the village of Nespelem, WA.

Yellowstone National Park is a place of wonder, beauty, and almost spiritual significance to all who look upon its enchanting landscape. But long before western society encroached upon its borders, indigenous people revered this land for its resources and cultural importance. The next time you find yourself driving along Wyoming Highway 296, also known as the Chief Joseph Scenic Byway, on your way to visit Yellowstone National Park, remember the flight, and plight, of the Nez Perce, who walked the very trail upon which you drive.

You can visit numerous Nez Perce Commemorative Sites of Nez Perce National Historical Park along the 1,170-mile Nez Perce National Historic Trail, stretching from Wallowa Lake, Oregon, to the Bear’s Paw Mountains, Montana. For more details, see https://www.nps.gov/nepe/index.htm.

North American Indian regional losses 1850 thru 1890.

My people have lived in the Amazon for 6,000 years: You need to listen to us — #Climate Home News

Indigenous leader and activist Txai Suruí (Photo: Gabriel Uchida )

Click the link to read the article on the Climate Home News website (Txai Suruí):

Everything I know and love about nature has been passed down to me from my ancestors.

I am only 25 years old but my people have been living in the Amazon rainforest for at least 6,000 years. I follow our ancient traditions that allow us to live in harmony with nature and protect the rainforest in which we live.

When corporations look at my home in the Amazon rainforest, they don’t see the intricacies of the trees’ roots, the way they weave their way in and out of rich soil. They don’t pay attention to the sound of raindrops as they hit leaves, small and large. They do not see a land capable of sustaining life on Earth, a land that needs protection, a land that is sacred. Instead, they see commodities.

Today, my peoples’ mission to protect nature is becoming impossible. The climate is warming rapidly, the animals are disappearing and the flowers are not blooming like they did before.

And when we try to protect our environment from the powers that be, we are bullied, harassed, and sometimes even murdered.

My childhood friend, Ari Uru-eu-wau-wau, was murdered for protecting the forests from illegal loggers, farmers and miners. His story is shared in a documentary I helped produce called The Territory. It was co-produced by the Indigenous Uru-Eu-Wau-Wau people and chronicles their struggle to defend the land on which Ari and his ancestors have lived for millennia.

The murder of British journalist Dom Phillips and indigenous expert Bruno Pereira in the Amazon is not an isolated case. It’s a tragedy that there are so many other cases like this.

My husband is also a journalist based in the Amazon and he has received death threats for reporting on illegal activities. My father, my mother and so many of my friends also face regular intimidation and threats for defending their ancestral land.

The justice we are calling for extends beyond those holding the guns that are killing Earth defenders. We want Brazil’s leaders whose actions or lack thereof, are allowing this violence to go rampant, to be held to account too.

Since President Jair Bolsonaro took office in Brazil three years ago, his administration has made it a priority to weaken environmental protections. The government agency supposed to protect Indigenous Peoples’ rights, was turned against us. This has resulted in grim records for deforestation in Brazil.

Despite the government’s pledges at Cop26 to end and reverse deforestation by 2030, the Brazilian Amazon saw a 64% jump in deforestation in the first three months of 2022 compared to the previous year – which was already up from the year before that.

Although international pressure from companies and countries which buy agricultural products from Brazil has increased, we cannot ignore the fact that several multinational corporations are still profiting from the anti-environment and anti-indigenous legislation being pushed in Brazil.

That’s why my father, the great Chief Almir Suruí, together with Chief Raoni Metuktire of the Kayapo people, presented a formal request to the International Criminal Court in The Hague last year to investigate what is happening in Brazil. They are demanding that those responsible are held accountable for crimes against humanity.

As we wait for a decision, we wonder: will our evidence be taken seriously? Will the countries that promised to uphold human rights and protect the Earth keep their word? How many more will be killed in a senseless war on the environment and those who protect it before things change?

And much like we must protect peoples’ rights, we need to defend the ecosystems that support us. This is why I am calling on the international community to request the International Criminal Court to recognise the crime of ecocide. Courts around the world have long claimed that they want to fight environmental crime. Now they have the chance to turn their words into actions and recognise the attacks against my home in the Amazon for what they are: ecocide.

I ask world leaders, especially from the Global North: Have you given up living on Earth? Why do indigenous peoples have to protect more than 80% of the world’s biodiversity with so little support while the rich dream of colonising other planets?

The mistakes that have brought us to this climate crisis are a heavy burden. But you cannot run away from it. We can still fight! Join us and support indigenous land defenders.

I have been raised with the understanding that in order to live harmoniously on this planet we must listen to the stars, the moon, the wind, the animals and the trees. We must listen to the Earth. She is speaking and her message is clear: we have no time to waste.

Txai Suruí is an Indigenous leader and activist from the Brazilian Amazon. She leads the Rondônia Indigenous Youth Movement and the Kanindé Association and is the executive producer of the award-winning documentary The Territory.