August 2020 #ENSO update: ahoy, mateys — @NOAA

From NOAA (Emily Becker):

The chance of La Niña developing this fall is up slightly from last month, at around 60%. Our La Niña Watch continues!

Becalmed
The Oceanic Niño Index—the three-month mean sea surface temperature anomaly (difference from the long-term mean, 1986-2015 in this case) in the Niño3.4 region—was -0.2°C during May–July 2020. The Oceanic Niño Index is our official metric for ENSO (El Niño/Southern Oscillation). -0.2°C is solidly in the “neutral” category of greater than -0.5°C and less than 0.5°C, so we continue in ENSO-neutral conditions for now.

Monthly sea surface temperature in the Niño 3.4 region of the tropical Pacific for 2019-2020 (purple line) and all other years starting from neutral winters since 1950. Climate.gov graph based on ERSSTv5 temperature data.

The current 60% chance of La Niña is largely based on the dynamical computer models, most of which slightly favor La Niña in the fall and winter.

Fair winds and following seas
The near-surface winds over the equatorial region—the trade winds—blow steadily from the east to the west near the equator. Well, I always describe them that way, but technically they blow from the northeast to the southwest on the north side of the equator, and from the southeast to the northwest south of the equator! (You can see why I simplify it sometimes, especially since the easterly component is what matters the most for ENSO.)

The trades result from the Hadley circulation—when heated air rises in the tropics, it ascends to the upper level of the atmosphere and then travels to the north and south. It descends again in the mid-latitudes, and travels back toward the equator near the surface.

The Hadley circulation, in which heat is transferred from the Earth’s surface to the upper atmosphere through convection and latent heating. Map by NOAA Climate.gov.

Because the Earth is spinning, the winds traveling toward the equator are bent to the right in the northern hemisphere and to the left in the southern hemisphere (the Coriolis effect). The Earth spins eastward, so winds headed toward the equator veer off to the west—the opposite direction of Earth’s rotation.

The Pacific warm pool and trade winds. NOAA Climate.gov map from the Data Snapshots map collection.

The trade winds help to keep warmer water piled up in the western side of the tropical Pacific (the Pacific warm pool), and we keep a close eye on them for ENSO prediction. When they relax, the surface water warms, and warmer-than-average water can shift eastward under the surface. (Form of: a downwelling Kelvin wave!) When they’re stronger than average, they can cool the surface, and result in an upwelling Kelvin wave: cooler-than-average subsurface water moving eastward.

Recently, the trades have been stronger, and the surface has cooled in the east-central Pacific Ocean. Also, the amount of cooler water under the surface has begun to increase again, which is a bit of a relief for forecasters, because it had been diminishing when we issued the La Niña Watch last month. This development supports the models’ forecast of La Niña, since cooler subsurface water will reinforce the surface cooling.

Daily near-surface (950 hPa) wind anomalies in the central Pacific, averaged over the area 5S-5N, 170E – 200E. January 1st 2020 is at the bottom of the graph, and August 6th 2020 is at the top. Purple areas show where the trade winds were stronger than average, while orange areas indicate weaker than average. Climate.gov image from CPC data.

Red sun in morning
As always, the world’s oceans have a lot going on.

July 2020 sea surface temperature departure from the 1981-2010 average. Image from Data Snapshots on Climate.gov.

Of course, we’ll note the slightly cooler-than-average water in our tropical Pacific ENSO monitoring regions. Also, though, you can see the warm tropical Atlantic, one of the major factors in NOAA’s updated Atlantic Hurricane Seasonal Outlook, which expects an “extremely active” season. Another element is our increased chance for La Niña, since La Niña conditions reduce wind shear over the tropical Atlantic. Shear, the difference between winds near the surface and high up in the atmosphere, makes it hard for hurricanes to form and grow.

It’s also hard to miss the large red area in the northeastern Pacific. This certainly caught my eye, and I reached out to our NOAA colleagues and marine heatwave experts Mike Jacox and Andy Leising to find out more. They confirmed that this is a marine heatwave, a prolonged warm water event. “This current one has been going on since early June. It’s really like this whole series of [marine] heatwaves we’ve had this spring and summer are just continuations of the 2019 event,” said Andy.

The current heatwave formed in the same location as the previous one. Andy went on to say “our current idea is that it’s very likely there is considerable sub-surface heat out there left over from previous heatwaves, which makes initiation of subsequent heatwaves easier.” Check out Andy’s Blobtracker website (props for an excellent name!) for more info.

Walk the plank
What’s with all the nautical nonsense in this post? I recently returned from a sailboat trip through the mid-Atlantic Intracoastal waterway, so I have water on my mind even more than usual! Thanks for staying on board with us on the good ship ENSO.

Calm July morning on the Alligator River, NC. Photo by Emily Becker.

@USBR begins constructing water system under Aamodt Indian Water Rights Settlement #RioGrande

Albuquerque Area office Archaeologist Larry Moore oversees initial excavation at the Pojoaque Basin Regional Water System construction site. Photo credit: Bureau of Reclamation

Here’s the release from Reclamation (Mary Carlson):

POJOAQUE, N.M. – The Bureau of Reclamation began construction on August 10, 2020 on a water system that will bring clean drinking water to approximately 10,000 people and ensure a reliable water supply for residents of the Pueblos of Pojoaque, Nambé, San Ildefonso and Tesuque, as well as some residents of Santa Fe County.

“This is an exciting day for Reclamation and all Aamodt Indian Water Rights Settlement parties,” said Commissioner Brenda Burman. “Countless hours of hard work and coordination between the many partners led to this moment, and we can now begin building this water system.”

Construction officially began this week at the water intake features on San Ildefonso Pueblo. Phase one of the project includes water intake structures, a control building, 20 miles of water conveyance pipeline, three water storage tanks and a water treatment plant on San Ildefonso, Pojoaque and Nambe Pueblos.

“The start of the construction of the Pojoaque Basin Regional Water System is a milestone that we at the Pueblo de San Ildefonso have heard and talked about for many years and it is hard to believe that it is finally happening. This is because the Pueblo has been involved in the Aamodt water rights litigation for decades and the regional water system is a core part of that settlement that previous San Ildefonso Governors and Tribal Council members have long discussed, debated, negotiated and fought for because the regional water system will insure clean drinking water for our Pueblo community and others in the Pojoaque Basin,” said Pueblo de San Ildefonso Governor Perry Martinez. “The Pueblo de San Ildefonso, along with leaders from my sister Pueblos of Nambe, Pojoaque and Tesuque, and our partners at the County of Santa Fe, the City of Santa Fe and the State of New Mexico have worked diligently for many years and overcame many hurdles to get to this point and I applaud everyone’s efforts today.”

The water system will divert water from the Rio Grande in northern New Mexico. The system will include water treatment facilities, along with storage tanks and transmission and distribution pipelines with the capability to supply up to 4,000 acre-feet per year (about 3.57 million gallons per day) of drinking water.

The Pojoaque Basin Regional Water System is part of the Aamodt Settlement Agreement and was authorized by Congress under the Aamodt Litigation Settlement Act of 2010 to settle Indian water rights disputes in the Pojoaque Basin.

“The Pueblo of Nambé is pleased that the construction of the Pojoaque Basin Regional Water System is beginning, marking a significant step toward implementation of the Aamodt water rights settlement. Construction of the Regional Water System represents the cooperative resolution of over more than four decades of litigation,” said Nambe Pueblo Governor Phillip A. Perez. “The Pueblo, together with the Pueblos of Pojoaque, San Ildefonso and Tesuque, and their partners the County of Santa Fe, the City of Santa Fe and the State of New Mexico are finally starting construction of a water system that will provide reliable, clean water to the four Pueblos and the residents of the Pojoaque Basin. On behalf of the Pueblo of Nambé, please join me in celebrating this important occasion.”

“We are excited to finally begin constructing this vitally important project that will soon deliver a firm, reliable, and safe water supply to all the Aamodt settlement parties in the Pojoaque Valley,” said New Mexico State Engineer John D’Antonio.

“Santa Fe County applauds this significant step forward toward completion of the Pojoaque Basin Regional Water System, the signature feature of the Aamodt Settlement which will bring a new source of safe and reliable drinking water to the Pojoaque Basin. We look forward to working with all of our partners and the Bureau of Reclamation to ensure sufficient federal funds are authorized to complete the project beyond this stage of limited construction,” said Santa Fe County Manager Katherine Miller.

Navajo Dam operations update: Releases to bump to 1,000 CFS August 14, 2020 #ColoradoRiver #COriver #aridification

The San Juan River’s Navajo Dam and reservoir above.U.S. Bureau of Reclamation

From email from Reclamation (Susan Behery):

In response to decreasing flows and a continued dry forecast weather pattern in the San Juan River Basin, the Bureau of Reclamation has scheduled an increase in the release from Navajo Dam from 900 cubic feet per second (cfs) to 1,000 cfs on Friday, August 14th, starting at 5:00 PM. Releases are made for the authorized purposes of the Navajo Unit, and to attempt to maintain a target base flow through the endangered fish critical habitat reach of the San Juan River (Farmington to Lake Powell).

The San Juan River Basin Recovery Implementation Program has recommended flows in the critical habitat reach as close to 500 cfs as possible for the summer of 2020. This is within their normal recommended range of 500 to 1,000 cfs. This target base flow is calculated as the weekly average of gaged flows throughout the critical habitat area from Farmington to Lake Powell.

The time to prepare for drought is not during a #drought — the Fence Post

Storm clouds gather as cows graze at the USDA-ARS Central Plains Experimental Range near Nunn, Colo.
Photo by David Augustine/USDA-ARS via the Fence Post

From the Fence Post (Amy Hadachek):

It’s the story of big climatological differences across Nebraska, as the state comes off of a year of records in 2019, with last year (2019) being the third wettest on record, while drought currently covers the western one-third of Nebraska, as well as northeast Nebraska and south central Nebraska.

“2019 was exceptional, with highly impactful weather events,” said Martha Shulski, director of the Nebraska State Climate Office and associate professor in the School of Natural Resources, University of Nebraska-Lincoln, who was a key speaker during the virtual 20th annual Nebraska Grazing Conference on Aug. 11. “Timing and location of precipitation can mean everything. It wasn’t just a storm that caused the major impact in Nebraska last year, we had a cold, wet winter, a lot of snow on the ground, frozen soils, and rapid melting that all led to major impacts.”

Shulski discussed past, current and future climate trends, noting Nebraska’s temperatures are more variable than global averages.

THE FORECAST

How will 2020 finish out? Some eyebrow-raising answers begin with temperatures trending higher than normal for 2020 in Nebraska…

For autumn, the Climate Prediction Center’s outlook for September, October and November 2020 favors warmer than normal temperatures from western Kansas into the Rocky Mountain states. Precipitation points to wet (in North Dakota), however below-average precipitation is forecast for the Rocky Mountain states, southwest Nebraska, and the western half of Kansas and Oklahoma.

“We also expect the warming in Nebraska to increase at an unprecedented rate, than what it’s been historically,” Shulski said. “We expect a shift of drier conditions in summer, with a wetter winter and spring, and more extremes with Nebraska’s climate future.” Her climate prediction includes a longer growing season by several weeks with more evaporative demand with an increased water requirement, longer summers, hot nights, more hot days with more extreme rainfall events.

“The magnitude of expected changes will exceed those experienced in the last century. Regarding large scale events, luckily we’ve been pretty wet (2019) so we have a fair amount of water in soil profile. So when we dried out with high winds and evaporative conditions, it was actually okay since we came off a very wet year, she said.

To deal with the new weather outlook, Shulski said producers should plan for overall warmer and wetter climate punctuated by droughts and weather extremes, which she expects to see magnified in the future…

RANGELAND PRODUCTION

There are a couple things that set the benchmark, in terms of exceptionally low rangeland production. When the ‘climate drivers’ Pacific Decadal Oscillation and El Nino Southern Oscillation (ENSO) are both in cool phases together, dry conditions occur about 50 percent of the time, said Justin Derner, research leader for the USDA-ARS Rangeland Resources and Systems Research Unit. Derner was also a speaker during the Nebraska Grazing Conference.

In the Great Plains, 1934 and 1956 were two of the worst years in 20th century records with tremendous soil loss and erosion.

Precipitation has increased the past 30 years across Nebraska except for places in the Nebraska Panhandle.

High Plains Drought Monitor August 11, 2020.

@USDA Announces Changes to Emergency Haying and Grazing Provisions, August 7, 2020

Photo credit: Aspen Journalism

Here’s the release from the Department of Agriculture:

WASHINGTON, Aug. 7, 2020 — The U.S. Department of Agriculture’s (USDA) Farm Service Agency (FSA) today announced changes for emergency haying and grazing of acres enrolled in the Conservation Reserve Program (CRP). This includes changes outlined in the 2018 Farm Bill that streamlines the authorization process for farmers and ranchers.

“FSA authorizes emergency haying and grazing of Conservation Reserve Program acres under certain conditions to provide emergency relief to livestock producers in times of severe drought or similar natural disasters,” said FSA Administrator Richard Fordyce. “These program changes will simplify the authorization process with an automatic trigger by severe drought designation, allowing livestock producers to quickly access much-needed forage.”

Program Changes

Previously emergency haying and grazing requests originated with FSA at the county level and required state and national level approval. Now approval will be based on drought severity as determined by the U.S. Drought Monitor.

To date, 500 counties nationwide have triggered eligibility for emergency haying and grazing on CRP acres. A list by state and map of eligible counties are updated weekly and available on FSA’s website.

Producers located in a county that is designated as severe drought (D2) or greater on or after the last day of the primary nesting season are eligible for emergency haying and grazing on all eligible acres. Additionally, producers located in counties that were in a severe drought (D2) status any single week during the last eight weeks of the primary nesting season may also be eligible for emergency haying and grazing unless the FSA County Committee determines that forage conditions no longer warrant emergency haying and grazing.

Counties that trigger for Livestock Forage Disaster Program (LFP) payments based on the U.S. Drought Monitor may hay only certain practices on less than 50% of eligible contract acres. Producers should contact their local FSA county office for eligible CRP practices.

Counties that don’t meet the drought monitor qualifications but have a 40% loss of forage production may also be eligible for emergency haying and grazing outside of the primary nesting season.

CRP Emergency Haying and Grazing Provisions

Before haying or grazing eligible acres, producers must submit a request for CRP emergency haying or grazing to FSA and obtain a modified conservation plan from the Natural Resources Conservation Service (NRCS).

Emergency grazing is authorized for up to 90 days and emergency haying is authorized for up to 60 days. Program participants must stop haying and grazing 30 days before the first freeze date in the fall based on the dates established for LFP.

Under the emergency grazing provisions, producers can use the CRP acreage for their own livestock or may grant another livestock producer use of the CRP acreage. The eligible CRP acreage is limited to acres located within the approved county.

For emergency haying, producers are limited to one cutting and are permitted to sell the hay. Participants must remove all hay from CRP acreage within 15 days after baling and remove all livestock from CRP acreage no later than 1 day after the end of the emergency grazing period. There will be no CRP annual rental payment reduction for emergency haying and grazing authorizations.

More Information

For more information on CRP emergency haying and grazing visit fsa.usda.gov/crp or contact your FSA county office. To locate your FSA office, visit farmers.gov/service-locator. For more disaster recovery assistance programs, visit http://farmers.gov/recover.

All USDA Service Centers are open for business, including some that are open to visitors to conduct business in person by appointment only. All Service Center visitors wishing to conduct business with the FSA, Natural Resources Conservation Service or any other Service Center agency should call ahead and schedule an appointment. Service Centers that are open for appointments will pre-screen visitors based on health concerns or recent travel, and visitors must adhere to social distancing guidelines. Visitors may also be required to wear a face covering during their appointment. Field work will continue with appropriate social distancing. Our program delivery staff will be in the office, and they will be working with our producers in office, by phone and using online tools. More information can be found at http://farmers.gov/coronavirus.

As Record Arctic Heat Continues, Canada’s Last Intact Ice Shelf Collapses — Yale 360 #ActOnClimate #KeepItInTheGround

The Milne Ice Shelf in Canada lost nearly 40 percent of its ice over a two-day period in late July. ECCC CANADIAN ICE SERVICE

From Yale360:

Canada’s last fully intact ice shelf in the Arctic has collapsed, shrinking by about 80 square kilometers, or 40 percent of its area, over just two days at the end of July, according to scientists at the Canadian Ice Service. The breakup of the ice was driven by record-setting temperatures in the region, which have measured 5 degrees Celsius (9 degrees Fahrenheit) above the 30-year average this summer.

“Entire cities are that size. These are big pieces of ice,” Luke Copland, a glaciologist at the University of Ottawa who was part of the research team studying the Milne Ice Shelf, located on Ellesmere Island in the Canadian territory of Nunavut, told Reuters. “This was the largest remaining intact ice shelf, and it’s disintegrated, basically.”

A research camp was lost in the collapse of the ice shelf. So was the northern hemisphere’s last known epishelf lake, a freshwater lake damned by ice that floats atop salty ocean water. In addition, two of Canada’s ice caps, located on the Hazen Plateau in St. Patrick Bay, disappeared completely this summer, two years earlier than scientists predicted, according to the National Snow & Ice Data Center (NSIDC) in Boulder, Colorado.

“When I first visited those ice caps, they seemed like such a permanent fixture of the landscape,” Mark Serreze, director of NSIDC and a geographer at the University of Colorado, Boulder, said in a statement. “To watch them die in less than 40 years just blows me away.”

The Arctic has warmed at a rate twice the global average in recent decades, but scientists say this summer has been even more extreme. In July, Arctic sea ice hit its lowest recorded extent. And the Russian Arctic has experienced record heat and wildfires, with temperatures exceeding 100 degrees F in the Siberian town of Verkhoyansk in late June.

Aspinall Unit operations update: Baseflow target adjusted to 900 CFS, August 13, 2020 #ColoradoRiver #COriver #aridification

Blue Mesa Reservoir, Curecanti National Recreation Area. Photo credit: Victoria Stauffenberg via Wikimedian Commons

From email from Reclamation (Erik Knight):

Releases from the Aspinall Unit will be increased from 1600 cfs to 1650 cfs on Thursday, August 13th. Releases are being adjusted to raise flows back to the baseflow target in the lower Gunnison River. The actual April-July runoff volume for Blue Mesa Reservoir came in at 57% of average.

There is a drought rule in the Aspinall Unit Operations EIS which has changed the baseflow target at the Whitewater gage. The rule states that during Dry or Moderately Dry years, when the content of Blue Mesa Reservoir drops below 600,000 AF the baseflow target is reduced from 1050 cfs to 900 cfs. Therefore, the baseflow target for July and August will now be 900 cfs.

Flows in the lower Gunnison River are currently below the baseflow target of 900 cfs. River flows are expected to trend up toward the baseflow target after the release increase has arrived at the Whitewater gage.

Currently, Gunnison Tunnel diversions are 1050 cfs and flows in the Gunnison River through the Black Canyon are around 600 cfs. After this release change Gunnison Tunnel diversions will still be around 1050 cfs and flows in the Gunnison River through the Black Canyon will be around 650 cfs. Current flow information is obtained from provisional data that may undergo revision subsequent to review.