@NASA Visualizes the Dance of a Melting Snowflake

This visualization is based on the first three-dimensional numerical model of melting snowflakes in the atmosphere, developed by scientist Jussi Leinonen of NASA’s Jet Propulsion Laboratory in Pasadena, California. A better understanding of how snow melts can help scientists recognize the signature in radar signals of heavier, wetter snow — the kind that breaks power lines and tree limbs — and could be a step toward improving predictions of this hazard.

The model reproduces key features of melting snowflakes that have been observed in nature: first, meltwater gathers in any concave regions of the snowflake’s surface. These liquid-water regions merge as they grow and eventually form a shell of liquid around an ice core, finally developing into a water drop.

The visualization shows a typical snowflake less than half an inch (one centimeter) long. The snowflake is composed of individual ice crystals whose arms became entangled when they collided in the air. The extremities of the arms melt first because they are more exposed to heat from the surrounding air. Water first fills small cavities within the ice crystals, and then these overflow, allowing water to pool into droplets.

“I got interested in modeling melting snow because of the way it affects our observations with remote sensing instruments,” Leinonen said. A radar “profile” of the atmosphere from top to bottom shows a very bright, prominent layer at the altitude where falling snow and hail melt, much brighter than the layers above and below. “The reasons for this layer are still not particularly clear, and there has been a bit of debate in the community,” Leinonen explained.

Simpler models can reproduce the bright melt layer, but a more detailed model like this one can help scientists to understand it better, particularly how the type of melting snow and the radar wavelengths used to observe it relate to the brightness of the layer.

A paper on the numerical model, titled “Snowflake melting simulation using smoothed particle hydrodynamics,” recently appeared in the Journal of Geophysical Research – Atmospheres. Music: Creeping Cauldron by Benjamin James Parsons, Floating on Kisses by Lennert Busch, and Strangely Calm by Brice Davoll Complete transcript available.

This video is public domain and along with other supporting visualizations can be downloaded from the Scientific Visualization Studio at: http://svs.gsfc.nasa.gov/12908

Credit: NASA’s Goddard Space Flight Center/LK Ward

#Colorado Communities File Lawsuit Against Oil Giants for #ClimateChange Costs

Here’s the release (Barb Halpin, Public Information Officer, Ben Irwin, Amy Markwell, Valentina Stackl):

Costs of climate change impacts estimated to top one hundred million dollars by 2050

Today, the Colorado communities of Boulder County, San Miguel County, and the City of Boulder—with legal support from EarthRights International, Niskanen Center, and other co-counsel—filed a lawsuit against Suncor and ExxonMobil (“Exxon”), two oil companies with significant responsibility for climate change. The communities have demanded that these companies pay their fair share of the costs associated with climate change impacts, so that the costs do not fall disproportionately on taxpayers.

Climate change affects fragile high-altitude ecosystems and hits at the heart of these communities’ local economies, affecting roads and bridges, parks and forests, buildings, farming and agriculture, the ski industry, and public open space. Adapting to such a wide range of impacts requires local governments to undertake unprecedented levels of planning and spending. Over the next three decades, these communities will face at least one hundred million dollars in costs to deal with the impacts of climate change caused by the use of fossil fuel products like those made and sold by Suncor and Exxon.

Suncor and Exxon have known about the costly consequences of fossil fuel use for more than 50 years. Yet they continued to promote and sell their products, while recklessly deceiving the public and policymakers about the dangers.

In the past year, nine coastal communities in California and New York filed climate lawsuits against fossil fuel companies. This is the first such lawsuit in Colorado—or anywhere in the U.S. interior—aimed at holding fossil fuel companies accountable for paying their fair share of the costs of climate change.


“Climate change impacts are already happening and they are only going to get worse. In fact, Colorado is one of the fastest warming states in the nation. Climate change is not just about sea level rise. It affects all of us in the middle of the country as well.” – Elise Jones, Boulder County Commissioner

“We are a small rural county dependent on tourism and farming and ranching. A natural disaster here could wipe out our reserves. Unabated fossil fuel production is already impacting our climate. These changes will grow more intense over time.” – Hilary Cooper, San Miguel County Commissioner.

“Our communities and our taxpayers should not shoulder the cost of climate change adaptation alone. These oil companies need to pay their fair share.” – Suzanne Jones, Mayor, City of Boulder

“For over 50 years, Suncor and Exxon have known that fossil fuels would cause severe climate impacts. To enhance their own profits, they concealed this knowledge and spread doubt about science they knew to be correct. Now, communities all over this country are left to foot the bill.” – Marco Simons, EarthRights International

“Future generations and those least responsible for causing climate change will bear the brunt of the impacts. We need to shift the costs back to these companies that have profited off their demands for unabated pollution in the face of global climate destabilization.” – Micah Parkin (350 Colorado)

“The fossil fuel industry has normalized oil and gas in our lives while concealing the dangers. It’s time for a cultural shift. In the future, when we talk about ‘energy,’ we should be referring to renewable energy, not fossil fuels.” – Rebecca Dickson, Sierra Club

“For hundreds of years, the common law has insisted that people who damage property should be held liable for their actions, and this case seeks no more than to protect property rights and the rule of law.” – David Bookbinder, Niskanen Center.


For years, these Colorado communities have taken action to reduce their own carbon footprints. All three have adopted ambitious CO2 emission reduction targets, passed budgets for climate work, conducted greenhouse gas (GHG) inventories, and established incentive programs for residents. Despite these efforts, taxpayers already face the rising costs of adapting to a changing climate.

Suncor and Exxon are two of the world’s largest contributors to climate change and have been particularly active in Colorado. Fossil fuel combustion accounted for nearly 80 percent of all GHG emissions between 1970 and 2010.

  • Exxon is the largest investor-owned fossil fuel producer in history. Suncor is one of the world’s largest independent energy companies. Both are active in Colorado.
  • Suncor’s U.S. operations are based in Denver, Colorado; the company supplies about 35 percent of the state’s gasoline and diesel fuel demand. Suncor and Exxon work closely together in Colorado to market and sell fossil fuels.
  • The two companies jointly own the majority of Syncrude Canada Ltd., one of the largest developer of Canada’s tar sands.
  • Together, Suncor and Exxon are responsible for billions of tons of CO2 emissions. Their future carbon footprint is likely to be enormous, as well: both companies plan to expand fossil fuel production through tar sands, fracking, and other means.

    For more than 50 years, these oil companies have known about the harm that their products would cause to communities, but have chosen to continue business as usual. These companies have long known about the risks of their own activities. In 1968, industry scientists warned them that “significant temperature changes are almost certain to occur by the year 2000” due to rising GHGs, and that “the potential damage to our environment could be severe.”

    By the 1970s, Suncor and Exxon knew with high certainty that their products were dangerous and that inaction would cause dramatic, even catastrophic, changes to the climate. Exxon even took measures to protect itself from climate change: for example, the company adapted its own facilities to protect from sea level rise.


    Boulder County, San Miguel County, and the City of Boulder have partnered together to represent communities on the Front Range and the Western Slope and require these oil companies to help pay for the costs of climate change on local communities in Colorado. Because of the magnitude of the financial impacts, these communities feel like they have little choice but to bring this litigation on behalf of their residents.

    States accuse @CAPArizona gaming #LakeMead, undermining #ColoradoRiver #drought plans #COriver

    View of Lake Mead and Hoover dam. Photo credit BBC.

    From The Nevada Independent (Daniel Rothberg):

    After expressing their frustration privately for weeks, negotiators for four Colorado River Basin states sent a strongly worded letter to Arizona water managers on Friday, singling out the actions of one state agency as “threaten[ing] the water supply for nearly 40 million people.”

    In the letter, the Upper Colorado River Commission said those actions could threaten efforts to conserve water and prevent Lake Mead from going into shortage for as long as possible. It could, they wrote, also undermine a decade of broader collaboration intended to avoid costly litigation between Colorado River users.

    In a second letter released on Monday, Denver Water told the Arizona water agency — the Central Arizona Project — that it is prepared to pull conservation funding because CAP’s actions “severely compromise the trust and cooperation that has allowed us to develop [the program].”

    The mounting pressure on CAP, which is operated by the Central Arizona Water Conservation District (CAWCD), comes as the agency is engaged in a fight within Arizona over how to manage the state’s Colorado River water. At issue is whether the Central Arizona Project, which delivers water to Tucson and Phoenix, is gaming a set of guidelines intended to balance the river’s reservoirs during times of drought. The Arizona Department of Water Resources, an arm of the governor’s office, has criticized CAP’s strategy for months and now other Colorado River users are piling on, warning the agency to stop before it jeopardizes delicate negotiations over drought planning.

    In response to the letters on Monday, Arizona’s top water official doubled down on his criticism. Tom Buschatzke, who directs the Arizona Department of Water Resources, said he shared some concerns in the letter and agreed CAP was manipulating the system to get more water from the Upper Basin.

    “I have huge concerns that the unilateral actions of CAWCD are threatening the regional and binational [drought] plans… that will benefit and protect Lake Mead,” Buschatzke said on Monday in response to the two letters.

    In a statement, CAP said it was “surprised and disappointed to have received a letter from the Upper Colorado River Commission questioning CAWCD’s intentions in leaving water in Lake Mead. We have been reaching out to our partners in the Upper Basin, hoping to clarify apparent misunderstandings, and to facilitate in-person, collaborative discussions aimed at finding solutions that will benefit the communities and environment served by this mighty river.”

    What’s going on here

    The Colorado River is split into an upper and a lower basin with two main reservoirs in each division — Lake Powell and Lake Mead. Under the 1922 Colorado River Compact, the Upper Basin states of Colorado, New Mexico, Wyoming and Utah are obligated to release a certain amount of Lake Powell water for the Lower Basin states of Arizona, California and Nevada.

    On top of that, the Upper Basin has agreed, in recent years, to send “bonus water” to Lake Mead if it is at a low elevation relative to Lake Powell. The dispute with CAP is about the “bonus water.” Recently, CAP has advocated in presentations for keeping Lake Mead at a “sweet spot” — high enough to avoid a shortage but low enough to get “extra water” from Lake Powell.

    This creates a political issue for the Upper Basin. It wants to store water in Lake Powell and boost the reservoir’s elevations. That way it can ensure full deliveries to the Lower Basin in dry years and continue producing hydropower.

    CAP is undermining efforts to keep water in Lake Powell, the letters argue, by adjusting how it orders water from Lake Mead (CAP’s general manager Ted Cooke defended this practice on Twitter last week as placing its “water order wisely”).

    The letter signed by representatives for all the Upper Basin states calls CAP’s action a “strategy to intentionally maximize demands within the Central Arizona Project to induce larger than normal releases from Lake Powell.” The “goal,” they wrote on Friday, “appears to be to delay agreement on drought plans in order to take advantage of what it terms the ‘sweet spot.’”

    Denver Water called it “unacceptable.” The municipal agency said that it would cancel funding for a Colorado River conservation program in the Upper Basin unless CAP “is able to verifiably establish it has ceased all actions to manipulate demands and is fully participating in aggressive conservation.”

    In recent months, Cooke has defended CAP’s decisions. CAP’s supporters see the actions as a water agency acting in its own interests. Cooke argued that it would be counterproductive to store more water in Lake Mead because that could boost its elevation so much that the Lower Basin would forgo any “bonus water.” Arizona would take the steepest cuts during a shortage. He has said the best thing to do is to get as much water from Powell as the current rules allow and use it to mitigate a shortage.

    From The Arizona Daily Star (Tony Davis):

    The agency that runs the $4 billion Central Arizona Project is being accused of manipulating Colorado River reservoirs’ operations to suck out more water for its Tucson, Phoenix and Pinal County customers.

    The accusation came in two letters in the past few days from representatives of four Upper Colorado River Basin states, the federal government and the Denver Water Dept. They say CAP’s approach threatens a Western water supply serving nearly 40 million people. It also threatens the harmony that has marked relations among the seven basin states since they approved guidelines to run the Colorado River’s reservoirs in 2007, they say.

    Under criticism is CAP’s practice of limiting how much river water it conserves each year, in order to prop up Lake Mead’s declining reservoir levels. The CAP has resisted pressure from other water agencies in Arizona to boost its conservation beyond about 200,000 acre-feet a year, enough to cover that many football fields a foot deep.

    CAP says that’s because as Lakes Mead and Powell are managed under the 2007 guidelines, conserving too much, or “overconserving” as CAP officials put it in the past, could reduce water releases from Powell to Mead. That would trigger shortages and cutbacks in water deliveries to Arizona users. CAP brings drinking water to Tucson and Phoenix and irrigation water to Pinal County via a 336-mile-long canal.

    That stance irks the Upper Colorado commission, representing the Upper Basin states of Colorado, Utah, New Mexico and Wyoming and the U.S. government.

    Last Friday, commissioners wrote that the Central Arizona Water Conservation District — a three-county water district running CAP — “intends to disregard the basin’s dire situation at the expense of Lake Powell and the other basin states.” CAP is trying to “maximize demands” to get larger water releases from Powell, said the letter to Arizona Department of Water Resources Director Tom Buschatzke.

    Officials of the CAP water district responded in a statement, “We are surprised and disappointed to have received a letter from the Upper Colorado River Commission questioning CAWCD’s intentions in leaving water in Lake Mead.” On Twitter, CAP general manager Ted Cooke recently said the agency places its water order wisely, following federal guidelines…

    Since 2014, CAP and its partners reduced water use enough to be able to leave more than 850,000 acre-feet in Mead, the statement said…

    In its letter, the Upper Colorado commission noted that because of a high water release expected from Powell this year and continued low snowpack and poor river runoff, Powell is expected to drop 30 feet in the next year. If these conditions persist, CAP’s efforts to boost water releases from Powell could make future reservoir conditions worse and trigger more severe shortages in the long term, the letter said…

    The letters were triggered by a graphic recently posted on CAP’s website, saying the agency has maintained a “sweet spot” for Lake Mead’s water levels.

    By that, it means conservation has kept Lake Mead high enough to avoid a shortage, but not so high as to cause the federal government to release only 8.23 million acre-feet of water each year — the customary average annual delivery from Powell to Mead. Instead, the feds have released 9 million acre-feet each of the past four years.

    The graphic, which the agency took down after it generated controversy, made Lake Mead’s level appear to be a bigger factor in determining water releases than the weather, which others disagree with.

    The Upper Colorado commission and Denver Water are also concerned that this conflict threatens an interstate program in which the feds, Lower Basin water agencies and Denver Water pay farmers and other users to use less water, with the savings held in Mead.

    This program has saved about 139,000 acre-feet of river water. But Denver Water is prepared to end its support of the conservation program unless, among other things, CAP can show “it has ceased all actions to manipulate demands and is fully participating in aggressive conservation measures,” Denver Water chief Jim Lochhead wrote to the CAP…

    Paul Orme, an attorney for four irrigation districts in Central Arizona, said he continues to support CAP. Farmers will be the first to lose water during a shortage and they’re more interested in year-to-year releases, Orme said.

    “What they are doing is permitted under the (2007) guidelines,” Orme said, referring to the CAP. “I know the Upper Basin says they’re not in the spirit of the guidelines, but they’re in the letter of the guidelines.”

    From KJZZ.com (Bret Jaspers):

    Here’s what the upper basin doesn’t like: the CAWCD aims to keep Lake Mead at a so-called “sweet spot.” If the level of the lake stays in that range, then under current agreements, more water comes down from Lake Powell.

    The Commissioners’ letter expressed deep concern that CAWCD “intends to disregard the basin’s dire situation at the expense of Lake Powell and all other basin states.” Don Ostler, executive director of the Upper Colorado River Commission, said bluntly in an interview. “That kind of manipulation is unacceptable to the Upper Basin.”


    CAWCD also reminded people of the water the agency has conserved on behalf of Lake Mead, “at a significant cost to CAP water users in terms of water and water rates.” CAWCD runs the Central Arizona Project canal system, which delivers water to the Phoenix and Tuscon areas…

    The Upper Colorado River Commissioners also urged Arizona to get its internal house in order so all seven states and Mexico can plan for long-term drought.

    “The seven Colorado River Basin states and Mexico are connected at the hip in this river,” Ostler said. “And what is going on with regards to one state, its failure to make progress, is having an effect on all seven states.”

    Buschatzke and Gov. Doug Ducey are trying to get big-ticket water legislation through the state Capitol this year. But time is running out on the legislative session.

    Click here to read Denver Water’s letter to the Central Arizona Project:

    From InkStain (John Fleck):

    Denver Water today joined state leaders in the Upper Colorado River Basin with a letter accusing the managers of the Central Arizona Project of manipulating water orders to get more water out of the Upper Basin’s reservoir at Lake Powell. The actions of the CAP’s managers “several compromise the trust and cooperation” needed to solve Colorado River problems, the letter from Denver Water’s Jim Lochhead said.

    Recap of the first Ogallala Water Summit

    From The Hutchinson News (Chance Hoener):

    When early explorers Zebulon Pike and Francisco de Coronado came upon the High Plains, they described it as a desert — an impossible region to farm.

    Irrigation changed that. It allowed residents to pull water from the Ogallala Aquifer, and grow crops nearly anywhere. The first irrigation wells in Kansas were drilled east of Garden City in 1908.

    The Ogallala is a massive, underground sponge, spanning from South Dakota and Wyoming, down through the High Plains to west Texas and New Mexico. Over 27,000 of the total 35,000 wells with active water rights in Kansas overlie the Ogallala, with 87 percent used for irrigation.

    But decades of pumping water out, with little return, has taken its toll.

    After 110 years of drilling and draining, the world’s largest aquifer is drying up.

    The Ogallala is the primary source of water for western Kansas farms, ranches and some communities, but projections indicate several areas that will go dry within 25 to 50 years at current usage rates. Some regions in Haskell County may have a decade or less…

    The Ogallala Aquifer Summit was organized by Colorado State University’s Ogallala Water CAP Program — a coordinated agriculture project funded by the United States Department of Agriculture – National Institute of Food and Agriculture. The summit brought together scientists, government agents and producers from the eight states situated over the Ogallala to discuss shared challenges and current initiatives to preserve the aquifer.

    Conversations between states had a rocky start, partly because they were spurred out of litigation regarding the Republican River basin along the Colorado, Nebraska and Kansas borders. The conflict led to monthly meetings of the Republican River Compact Administration — comprised of one member from each state — to change the approach and improve water management.

    “No offense to those that are here, but I’m just excited to come to an interstate water conference that doesn’t have more lawyers than it does farmers and ranchers,” Kansas Secretary of Agriculture Jackie McClaskey said to applause from the summit crowd.

    Nebraska Natural Resources Program Director Jesse Bradley and Colorado Commissioner of Agriculture Don Brown joined McClaskey for the first panel of the summit, discussing the cultivation of interstate conversations.

    Brown joked that the whole problem was Nebraska’s fault — Nebraska native Frank Zybach invented center pivot irrigation while living in Colorado — and Bradley fired back that ‘you always blame the upstream state.’

    She credits interstate conversations regarding the Republican River as a critical factor for changing the tone of the discussion. Instead of fighting over the water, the group is now working together to preserve water.

    “The biggest way we learned this lesson is from the complete 180 we’ve done on the Republican River discussions,” McClaskey said. “In July 2014, we started meeting month-to-month and created a true, long-term agreement, and are using those lessons to expand to all the states.

    “Now, I would call my colleagues from Nebraska and Colorado friends, which may not seem like a big deal, but it’s a lot easier to solve a problem with a friend than with an enemy.”