Wednesday, February 28, 2018

Wednesday, Feb 28

Global surface temperature relative to 1880-1920 based on GISTEMP analysis (mostly NOAA data sources, as described by Hansen, J., R. Ruedy, M. Sato, and K. Lo, 2010: Global surface temperature change. Rev. Geophys., 48, RG4004.  We suggest in an upcoming paper that the temperature in 1940-45 is exaggerated because of data inhomogeneity in WW II. Linear-fit to temperature since 1970 yields present temperature of 1.06°C, which is perhaps our best estimate of warming since the preindustrial period.

Reforesting US Topsoils Store Massive Amounts of Carbon, with Potential for Much More

U-M ecologist and biogeochemist Luke Nave demonstrates methods to measure soil carbon during a July 2015 workshop at the University of Michigan Biological Station. (Image Credit: Kailey Marcinkowski, Northern Institute of Applied Climate Science) Click to Enlarge.
Forests across the United States -- and especially forest soils -- store massive amounts of carbon, offsetting about 10 percent of the country's annual greenhouse gas emissions and helping to mitigate climate change.

But for more than 20 years, experts have warned that the strength of this carbon "sink" is declining and will level off around mid-century.  One way to compensate for the declining sink strength of U.S. forests is to add more trees -- by actively replanting after disturbances like wildfires or by allowing forests to retake marginal croplands, for example.

A study scheduled for online publication the week of Feb. 26 in Proceedings of the National Academy of Sciences provides the first empirically based, published estimate of the total amount of carbon currently accumulating in the topsoil of U.S. forests undergoing these two types of reforestation.

The University of Michigan-led research team also looked at the potential to expand carbon sequestration in reforesting areas.

"Where reforestation is happening -- either through planting of trees or through encroachmen t-- these lands are actively adding carbon to a large pool that will continue to grow for many decades," said U-M ecologist and biogeochemist Luke Nave, the study's lead author.

"The topsoils of reforesting lands provide a significant long-range solution to the problem of the declining carbon-sink strength of U.S. forests, and they help to mitigate climate change.  Even modest increases in the amount of land being reforested would have a multiplicative impact on nationwide carbon sequestration."

The researchers found that reforesting topsoils across the country are currently adding 13 million to 21 million metric tons (13-21 teragrams) of carbon each year, an amount equivalent to about 10 percent of the total U.S. forest-sector carbon sink and offsetting about 1 percent of all U.S. greenhouse gas emissions.

Over the next century, reforesting U.S. topsoils will sequester a cumulative 1.3 to 2.1 billion metric tons (1.3-2.1 petagrams) of carbon, accounting for nearly half of the soil-carbon gains occurring on U.S. forestland, said Nave, an assistant research scientist at the U-M Biological Station and in the Department of Ecology and Evolutionary Biology.

And the amount of stored carbon could increase dramatically if the nation's reforesting acreage, currently at nearly 200,000 square miles, grows.

Read more at Reforesting US Topsoils Store Massive Amounts of Carbon, with Potential for Much More

Tuesday, February 27, 2018

Tuesday, Feb 27

Global surface temperature relative to 1880-1920 based on GISTEMP analysis (mostly NOAA data sources, as described by Hansen, J., R. Ruedy, M. Sato, and K. Lo, 2010: Global surface temperature change. Rev. Geophys., 48, RG4004.  We suggest in an upcoming paper that the temperature in 1940-45 is exaggerated because of data inhomogeneity in WW II. Linear-fit to temperature since 1970 yields present temperature of 1.06°C, which is perhaps our best estimate of warming since the preindustrial period.

Climate Value of Earth's Intact Forests

Intact Forest Landscapes (Credit: intactforests.org) Click to Enlarge.
New research published today in Nature Ecology & Evolution demonstrates the extraordinary value of Earth's remaining intact forests for addressing climate change and protecting wildlife, critical watersheds, indigenous cultures, and human health.  Yet the global policy and science communities do not differentiate among the relative values of different types of forest landscapes -- which range from highly intact ones to those which are heavily logged, fragmented, burnt, drained and/or over-hunted -- due in part to the lack of a uniform way of measuring their quality.

With over 80 percent of forests already degraded by human and industrial activities, today's findings underscore the immediate need for international policies to secure remaining intact forests -- including establishing new protected areas, securing the land rights of indigenous peoples, regulating industry and hunting, and targeting restoration efforts and public finance.  Absent specific strategies like these, current global targets addressing climate change, poverty, and biodiversity may fall short, including the United Nations' Sustainable Development Goals to sustainably manage forests, combat desertification, halt and reverse land degradation, and halt biodiversity loss.

"As vital carbon sinks and habitats for millions of people and imperiled wildlife, it is well known that forest protection is essential for any environmental solution -- yet not all forests are equal," said Professor James Watson of WCS and the University of Queensland.  "Forest conservation must be prioritized based on their relative values -- and Earth's remaining intact forests are the crown jewels, ones that global climate and biodiversity policies must now emphasize."

Read more at Climate Value of Earth's Intact Forests

More Than 100 Cities Worldwide Now Powered Primarily by Renewable Energy

These cities get more than 70 percent of their electricity from wind, solar, geothermal and other renewables.  That’s up since the Paris climate agreement.


Burlington, Vermont, gets 100 percent of its power from renewable energy, including from solar farms like this one, built on locally made systems that track the sun. (Credit: Robert Nickelsberg/Getty Images) Click to Enlarge.
As the price of renewable energy drops, more cities are cutting the cord with fossil fuel-based electricity.

A new report released Tuesday by the environmental group CDP finds that more than 100 cities worldwide now get the majority of their power—70 percent or more—from renewables.  That's up from 42 in 2015, when countries pledged to cut greenhouse gas emissions in the Paris climate agreement.

CDP notes that more than 40 of those cities are now powered entirely by renewables, including Burlington, Vermont, which gets its electricity from a combination of wind, solar, hydro and biomass.  Burlington will have more company within the next 20 years—58 U.S. cities, including Atlanta and San Diego, having announced plans to do the same.

London-based CDP, which tracks climate-related commitments by corporations and governments, looked at 570 cities across the globe for the report.  The group defines renewables as solar, wind, hydro, wave power, biomass, geothermal—or all non-nuclear and non-fossil fuel sources—and includes cities where electricity from clean energy sources is citywide, not just in municipal buildings.

Four U.S. cities made the list of those getting at least 70 percent of their electricity from renewable sources: Seattle; Eugene, Oregon; and Aspen, Colorado, along with Burlington.  Five Canadian cities are also on the list:  Montreal, Vancouver, Winnipeg, North Vancouver, and Prince George, British Columbia.

Latin American Cities Lead the Way
As of now, Latin American cities lead the renewables charge, with much of their electricity coming from hydropower.  Of the cities getting at least 70 percent of their power from renewables, 57 percent are in Latin America, 20 percent are in Europe, 9 percent are in Africa, and 9 percent in North America.

North America also trails in investment dollars, spending $113 million to Europe's $1.7 billion, Africa's $236 million and Latin America's $183 million, CDP reports.

"Cities are responsible for 70 percent of energy-related CO2 emissions, and there is immense potential for them to lead on building a sustainable economy," Kyra Appleby, who leads the cities project for CDP, said in a statement.  "Reassuringly, our data shows much commitment and ambition.  Cities not only want to shift to renewable energy but, most importantly, they can."

Read more at More Than 100 Cities Worldwide Now Powered Primarily by Renewable Energy

Keeping Global Temperature Increase Below 1.5 Degrees Celsius Unlikely, Says IPCC Draft Report

Every September, the Intergovernmental Panel On Climate Change releases a report on global warming, but that report doesn’t take shape overnight.  It is the result of nearly a year’s worth of work compiling, editing, and digesting the latest research from around the world.  A draft of the report was available on the Federal Register in the US until recently.  Bear in mind this is a draft and may change in significant ways prior to final publication next September.  New studies published after the draft report was prepared but before May 15 may be included.  Nevertheless, the proposed report does not mince words.

Tom Toles thermometer (Credit: Toles) Click to Enlarge.There is a very high risk that under current emissions trajectories and current national pledges global warming will exceed 1.5°C above preindustrial levels.  Limiting global warming to 1.5°C would require a rapid phase out of net global carbon dioxide (CO2) emissions and deep reductions in non-CO2 drivers of climate change such as methane, with more pronounced and rapid reductions required than for limiting global warming to 2°C.  With a 66 percent probability, [keeping the increase below 1.5 degrees Celsius] lies beyond our capabilities.
Even if average global temperatures could be kept to 1.5 degrees C or below, “climate trends and changing extreme events in the oceans and over land imply risks for ecosystems and human societies even larger than today.”  According to Think Progress, the draft report claims only “rapid and deep” reductions in emissions together with aggressive carbon sequestration measures will forestall a more serious climate scenario.  “Delaying actions to reduce greenhouse gas emissions increases the risk of cost escalation…and reduced flexibility in future response options in the medium to long-term,” the draft reads.

“These may increase uneven distributional impacts between countries at different stages of development.”  To offset the effects of climate change on poorer nations and coastal areas, “all countries would need to significantly raise their level of ambition, shift financial flows and investment patterns, [and] improve coherence in governance,” according to the draft.  With a certified narcissist and sociopath in the White House, the odds of the US lifting a finger to help are virtually nonexistent.

There is some hope for America in the next national elections, in which progressives are showing strong early leads in many races, but those results could well be too little and too late to help the world avert an existential crisis.  Some experts suggest it will take $100 trillion dollars to solve the climate emergency.  Is that too high a price to pay to avoid extinction?

Read original at Keeping Global Temperature Increase Below 1.5 Degrees Celsius Unlikely, Says IPCC Draft Report

How Biofuels from Plant Fibers Could Combat Global Warming

An aerial image of the research study area in southwestern Kansas. (Credit: Colorado State University) Click to Enlarge.
Scientists, companies and government agencies are hard at work on decreasing greenhouse gas emissions that cause climate change.  In recent years, biofuels produced from corn have emerged as a fuel source to power motor vehicles and, perhaps, airplanes.

But corn is problematic as a biofuel source material.  It's resource-intensive to grow, creates many environmental impacts, and is more useful as food.

A study from Colorado State University finds new promise for biofuels produced from switchgrass, a non-edible native grass that grows in many parts of North America.  Scientists used modeling to simulate various growing scenarios, and found a climate footprint ranging from -11 to 10 grams of carbon dioxide per mega-joule -- the standard way of measuring greenhouse gas emissions.

To compare with other fuels, the impact of using gasoline results in 94 grams of carbon dioxide per mega-joule.

The study, High resolution techno-ecological modeling of a bioenergy landscape to identify climate mitigation opportunities in cellulosic ethanol production, was published online Feb. 19 in Nature Energy.

John Field, research scientist at the Natural Resource Ecology Lab at CSU, said what the team found is significant.  "What we saw with switchgrass is that you're actually storing carbon in the soil," he said.  "You're building up organic matter and sequestering carbon."

Read more at How Biofuels from Plant Fibers Could Combat Global Warming

Global Fossil Fuel Emissions of Hydrocarbons Are Underestimated

Evidence points to the need for a broader range of clean power beyond just wind and solar.


 Ethane (Credit: Adobe Stock) Click to Enlarge.
A growing number of US cities and states have proposed or even passed legislation that would require producing all electricity from renewable energy sources like solar and wind within a few decades.

That might sound like a great idea.  But a growing body of evidence shows it’s not.

It increasingly appears that insisting on 100 percent renewable sources—and disdaining others that don’t produce greenhouse gases, such as nuclear power and fossil-fuel plants with carbon-capture technology—is wastefully expensive and needlessly difficult.

In the latest piece of evidence, a study published in Energy & Environmental Science determined that solar and wind energy alone could reliably meet about 80 percent of recent US annual electricity demand, but massive investments in energy storage and transmission would be needed to avoid major blackouts.  Pushing to meet 100 percent of demand with these resources would require building a huge number of additional wind and solar farms—or expanding electricity storage to an extent that would be prohibitively expensive at current prices.  Or some of both.

The basic problem is that the sun doesn’t always shine and the wind doesn’t always blow.  The study analyzed 36 years’ worth of hourly weather data and found there are gaps in renewable-energy production even on a continental scale.

Relying on these intermittent sources alone would requiring building many more solar and wind farms to produce excess energy during particularly sunny and windy periods, plus huge storage systems that can bank hours’ or even weeks’ worth of power (see Serial Battery Entrepreneur’s New Venture Tackles Clean Energy’s Biggest Problem). Another possibility is to build long-distance transmission routes that could ship the electricity around the country at just the moment it’s needed.

Storage systems are incredibly expensive in the case of batteries—and geographically limited in the case of pumped hydroelectric, which requires a set of water reservoirs at varying heights (see Why Bad Things Happen to Clean-Energy Startups).  Long-distance transmission lines are also pricey and can take decades to get approved and built (see How to Get Wyoming Wind to California, and Cut 80% of US Carbon Emissions).

Just getting to 80 percent of demand reliably with only wind and solar would require either a US-wide high-speed transmission system or 12 hours of electricity storage.  A storage system of that size across the US would cost more than $2.5 trillion for a battery system.

To meet all the nation’s annual electricity needs with 99.97 percent reliability, utilities would have to build 12 hours of storage plus at least twice the amount of renewable-energy generation, the study found.  Or businesses could deploy slightly more wind and solar coupled with more than a month’s worth of storage.   

The advantage over renewables of other clean options, like nuclear or natural gas with carbon capture, is that they can provide always-on power or, at least in the latter case, can quickly ramp up and down to meet fluctuating demand (see Potential Carbon Capture Game Changer Nears Completion).

Read more at Global Fossil Fuel Emissions of Hydrocarbons Are Underestimated

Sea Level Rise Damaging More U.S. Bases, Former Top Military Brass Warn

The retired admirals and generals say climate change is putting key military facilities at risk of costly damage that could knock out critical operations for weeks.


 The Portsmouth Naval Shipyard in Maine is one of several military sites at risk from sea level rise, at new report from a panel of retired military officers warns. (Credit: U.S. Navy) Click to Enlarge.
A growing number of U.S. military sites are being damaged by sea level rise fueled by climate change, and that will threaten the military's ability to protect vital national security interests if the Pentagon and Congress don't take faster action, a panel of retired admirals and generals warns in a new report.

More than 200 domestic installations reported in a recent Defense Department assessment that they had been flooded by storm surges, compared to about 30 in 2008, the new report released Monday by the Center for Climate and Security says.

The report spotlights flooding and erosion risks to installations as diverse as the Marine Corps' boot camp at Parris Island in South Carolina, the nuclear submarine repair site in Portsmouth Naval Shipyard in Maine, and a missile defense system against possible attacks from Asia based in the Marshall Islands.  It's based on a synthesis of Congressional testimony by Pentagon officials and several federal studies in the last 18 months about the impact of climate change on national security.

"A number of coastal military bases and training sites are already experiencing the effects of sea level rise, tidal flooding and storm surge, and recent research shows that these effects are accelerating and will continue to do so more quickly than previously thought," said Heather Messera, who chaired the committee that wrote the report.

"Now is both the operationally practical and fiscally responsible time to act," she said.

Despite widespread denial of climate change in the Trump administration, led by the president himself, Defense Secretary James Mattis has said that climate change poses risks to global stability and national security.  So far, the Pentagon has been left alone as it works on improving the military's resilience to climate change.  But the efforts are patchy and often dependent on the priorities of installation commanders, which can vary from base to base, national security experts said.

A 2017 report by the federal Government Accountability Office concluded that the military is failing to properly plan for climate change and that bases seldom include foreseeable impacts into planning.  To date, the Pentagon has not concluded a full assessment "of sea level rise and broader climate impacts on U.S. military and national security," the new analysis says.  This, despite the fact that 1,774 military installations in the U.S. and abroad are in coastal areas.

"Many actions to adapt to climate change are happening sporadically, and those gaps should be addressed," said Francesco Femia, co-president of the Center for Climate and National Security, a Washington, D.C., think [tank] whose fellows include many former high-ranking military officers.  "It's up to our nation's policy makers to support the DoD."

Read more at Sea Level Rise Damaging More U.S. Bases, Former Top Military Brass Warn0

Relying on Renewables Alone Significantly Inflates the Cost of Overhauling Energy

Evidence points to the need for a broader range of clean power beyond just wind and solar.


A solar farm in Hughsville, Maryland supplies enough electricity for 600 homes. (Credit: Mark Wilson | Getty) Click to Enlarge.
A growing number of US cities and states have proposed or even passed legislation that would require producing all electricity from renewable energy sources like solar and wind within a few decades.

That might sound like a great idea.  But a growing body of evidence shows it’s not.

It increasingly appears that insisting on 100 percent renewable sources—and disdaining others that don’t produce greenhouse gases, such as nuclear power and fossil-fuel plants with carbon-capture technology—is wastefully expensive and needlessly difficult.

In the latest piece of evidence, a study published in Energy & Environmental Science determined that solar and wind energy alone could reliably meet about 80 percent of recent US annual electricity demand, but massive investments in energy storage and transmission would be needed to avoid major blackouts.  Pushing to meet 100 percent of demand with these resources would require building a huge number of additional wind and solar farms—or expanding electricity storage to an extent that would be prohibitively expensive at current prices.  Or some of both.

The basic problem is that the sun doesn’t always shine and the wind doesn’t always blow.  The study analyzed 36 years’ worth of hourly weather data and found there are gaps in renewable-energy production even on a continental scale.

Relying on these intermittent sources alone would requiring building many more solar and wind farms to produce excess energy during particularly sunny and windy periods, plus huge storage systems that can bank hours’ or even weeks’ worth of power (see Serial Battery Entrepreneur’s New Venture Tackles Clean Energy’s Biggest Problem).  Another possibility is to build long-distance transmission routes that could ship the electricity around the country at just the moment it’s needed.

Storage systems are incredibly expensive in the case of batteries—and geographically limited in the case of pumped hydroelectric, which requires a set of water reservoirs at varying heights (see Why Bad Things Happen to Clean-Energy Startups).  Long-distance transmission lines are also pricey and can take decades to get approved and built (see How to Get Wyoming Wind to California, and Cut 80% of US Carbon Emissions).

Just getting to 80 percent of demand reliably with only wind and solar would require either a US-wide high-speed transmission system or 12 hours of electricity storage.  A storage system of that size across the US would cost more than $2.5 trillion for a battery system.

To meet all the nation’s annual electricity needs with 99.97 percent reliability, utilities would have to build 12 hours of storage plus at least twice the amount of renewable-energy generation, the study found.  Or businesses could deploy slightly more wind and solar coupled with more than a month’s worth of storage.   

The advantage over renewables of other clean options, like nuclear or natural gas with carbon capture, is that they can provide always-on power or, at least in the latter case, can quickly ramp up and down to meet fluctuating demand (see Potential Carbon Capture Game Changer Nears Completion).

Read more at Relying on Renewables Alone Significantly Inflates the Cost of Overhauling Energy

Europe’s Cities Face a Hotter Century

British scientists have just issued a detailed hazard forecast for Europe’s cities, for increasing floods, droughts and heatwaves.


Athens is one European capital at greatest risk from both heat extremes and drought. (Image Credit: LennieZ, via Wikimedia Commons) Click to Enlarge.
Europe’s cities are about to bake.  The worst-case scenario for ever-hotter temperatures now suggests that later this century the Austrian city of Innsbruck – for example – could be subjected to heatwaves 14°C hotter than any in the past.

Altogether more than 400 cities could under such circumstances expect heatwaves at least 10°C hotter than any today.  Droughts in Europe could be 14 times worse than any droughts experienced today.

And some of Europe’s rivers could experience peak flows 80% higher than any today, which means ever-greater flood hazards, in particular for north-west European cities.

Three Europeans out of four live in cities.  By 2050 this proportion will be even higher:  82% will have moved to urban centers.

Researchers report in the journal Environmental Research Letters that they examined the trends for all 571 cities in Europe’s urban audit database and simulated the outcome of a range of climate predictions.

Read more at Europe’s Cities Face a Hotter Century

Europe Takes First Steps in Electrifying World’s Shipping Fleets

Container ships, tankers, freighters, and cruise liners are a significant source of CO2 emissions and other pollutants.  Led by Norway, Europe is beginning to electrify its coastal vessels – but the task of greening the high seas fleet is far more daunting.


The MS Ampere is one of Norway's two fully electric ferries. The country plans to launch another 60 by 2021. (Credit: Nce Maritime Clean Tech) Click to Enlarge.
If the electrification of the world’s automobile and truck fleet represents a daunting challenge, then converting the global shipping fleet from heavily polluting fuel oil and diesel to renewable sources of energy is no less complex.  It’s one thing to use electricity and lithium ion batteries to power a car ferry across a Norwegian fjord, with charging stations at both ends of the run.  It’s quite another to power the more than 50,000 tankers, freighters, and cargo carriers in the world’s merchant fleets across oceans.  International shipping now accounts for about 3 percent of global carbon dioxide emissions, and this could shoot up dramatically to 17 percent by 2050 if other sectors decarbonize while shipping emissions climb higher, as they have unremittingly in recent years.  The booming cruise ship industry has become a significant problem recently, emitting large quantities of carbon dioxide and sulfur dioxide, among other pollutants, according to the German environmental group, NABU.

Yet many analysts say that even though the technology to power large, ocean-going vessels on electricity is not yet ripe, the shipping industry’s conservative mindset is also a major impediment to the sector’s transformation.  “The industry doesn’t really believe that a switch from bunker fuels is possible,” says Faig Abbasov, a shipping expert with Transport & Environment — a Brussels-based international environmental organization — referring to the fuel oils used to power ships.  “And it’s countries with huge fleets that are obstructing changes that would drive forward the electrification of marine transport.”

Abbasov says the sector would change much more quickly if ship fuels were taxed — which they currently are not – and electricity for powering ships wasn’t taxed, as is currently the case across Europe.  “This means that ship owners sticking with the dirtiest fuels are given a free ride,” he says.

Despite these challenges, Norway is steadily making progress toward converting its shipping fleet to run on renewable energy.  “It’s really impressive — the transformation of shipping is beginning right now, it’s happening very fast, and not just in Norway,” says Borghild Tønnessen-Krokan, director of Forum for Development and Environment, an independent Norwegian NGO that has for years pushed for low-carbon transportation.  “Shipping is part of a bigger green revolution in transportation in Norway,” he added, noting that more than half of all Norwegian cars sold last year were hybrid or electric.

The flurry of activity in electric shipping may begin to address the glaring omission of shipping in the Paris Climate Accord, which did not cover maritime transport.  Shipping industry lobbyists and nations such as China and Brazil aggressively fought the inclusion of ship emissions in the accord, claiming that such a truly international sector couldn’t be held responsible for emissions in the same way that countries are.  The EU and the International Maritime Organization (IMO) have set up monitoring criteria and energy efficiency standards that will become more stringent over time, but the IMO, at the behest of the industry and high-profile shipping countries, has resisted meaningful and binding emissions reduction goals for shipping companies.  The EU has pushed back, threatening that it will include the sector’s CO2 pollution in its emissions-trading scheme if the IMO fails to take significant action.
...
Elsewhere in Europe, the electrification of maritime travel is gradually beginning to take off.  Late last year, Finland launched its first electric car ferry, and dozens of hybrid ferries and electric-powered ferries are scheduled to go into service in the coming years.  Finland’s cutting-edge maritime research vessel, the Aranda, has switched to hybrid propulsion.  The ship, which belongs to the Finnish Environment Institute (SYKE), has benefited in more ways than one from adding an electric power system.  The Aranda is equipped with a front-end ice-cutter that slashes through Arctic ice fields en route to monitoring stations and other winter research locations.  Since the electric motor has higher rotational force than the diesel motor, it is significantly more effective at powering the cutter to break up thick ice cover, says Jukka Pajala, a senior adviser at SYKE.  Moreover, the electric motor doesn’t expel pollutants that exacerbate the ice melt caused by global warming.  And the electric motor is virtually silent, a critical advantage for researching marine life. 

Denmark and Sweden are cooperating on two large eight-ton, electric passenger ferries that will travel the seven miles between Helsingborg, Sweden and Helsingör, Denmark.  This summer, the Dutch company Port-Liner will unveil five all-electric, driverless, emissions-free barges, dubbed the “Tesla ships,” that will navigate the canals linking the ports of Amsterdam, Antwerp, and Rotterdam.  The EU supported the 100 million-euro project with 8.5 million euros.

Despite these signs of progress, serious national and international regulations and incentives on converting the shipping industry to renewable sources of energy must be enacted, including a ban on heavy fuel oil in the Arctic to reduce the emissions of sooty, heat-absorbing pollution particles.  “The technology is there,” says Tønnessen-Krokan of Norway’s Forum for Development and Environment.  “Incentives have worked to make it happen, but there have to be sticks as well as carrots.  Shipping should have been subject to emissions targets years ago.”

Read more at Europe Takes First Steps in Electrifying World’s Shipping Fleets

Sunday, February 25, 2018

Sunday, Feb 25

Global surface temperature relative to 1880-1920 based on GISTEMP analysis (mostly NOAA data sources, as described by Hansen, J., R. Ruedy, M. Sato, and K. Lo, 2010: Global surface temperature change. Rev. Geophys., 48, RG4004.  We suggest in an upcoming paper that the temperature in 1940-45 is exaggerated because of data inhomogeneity in WW II. Linear-fit to temperature since 1970 yields present temperature of 1.06°C, which is perhaps our best estimate of warming since the preindustrial period.

Has the Arctic Finally Reached a Tipping Point?

Lone Ice in Arctic (Credit: earther.com) Click to Enlarge.
Something is not right in the Arctic.

The recent wave of mild, humid air and its attendant impacts is disturbing.  But this is the fourth winter where we’ve seen a veritable heat wave rack the Arctic.

The warm temperatures have also been accompanied by moist air, which has helped form clouds and lock in temperatures up to 60 degrees Fahrenheit above normal for extended periods in a typically dry, frozen climate.  Disappearing sea ice also means warmer ocean waters are exposed, further spinning the region out of whack.

Climate change is warming the Arctic twice as fast as the rest of the world.  We’ve known that for awhile.  The big question now is whether it’s pushing the Arctic past a tipping point into a new, altered state after four unprecedented winters.  And while scientists aren’t quite ready to say we’ve passed the point of no return, this unnerving string of winters has them quickly looking for more detailed answers about what’s happening so we can prepare for what comes next.

“Until recently, the seasonal sea ice maximum was relatively ignored; the September minimum got the attention,” Mark Serreze, director of the National Snow and Ice Data Center, told Earther.  “But that’s changing.  Strange things are happening in winter.”

This winter’s warm weather oddity is what NASA sea ice researcher Alek Petty called a “pincher attack.”  In previous winters, the heat has largely entered the Arctic through the North Atlantic between Greenland and Europe.  This winter, heat is pouring in there but also rushing through the Bering Strait from the North Pacific.  The double dose of heat is what’s creating wild records across the region, and winter temperatures have never been higher in recorded history.

UtqiaÄ¡vik, Alaska (formerly Barrow), a place that’s warmed so fast, scientists thought its weather station was broken, topped out at 31 degrees Fahrenheit on Tuesday.  Temperatures also swirled above freezing at the world’s northernmost land weather station.

Ice has disappeared from the Bering Sea when it would normally be growing.  The Chukchi Sea to the north has even see ice dip, an occurrence that’s only ever happened one other winter in recorded history.  The North Pole could see temperatures above freezing this weekend

Petty has conducted research into whether this type of supercharged heat has hit the Arctic in winters past.  He found that while these types of events have occurred before, their character has changed dramatically to resemble a heat wave on steroids.

“The key is they’re happening more frequently, lasting longer, and their intensity is increasing,” he told Earther.  “It’s this triple whammy of factors.”

Read more at Has the Arctic Finally Reached a Tipping Point?

Seas Will Rise for 300 Years

And the longer it takes to reduce carbon emissions, the higher they will go.


Seashore [Credit: Erika Maldonado Flickr (CC BY 2.0)] Click to Enlarge.
It's a given of climate change that greenhouse gases emitted today will shape the world for future generations.  But new research underscores just how long those effects will last.

A striking new study published Tuesday in the journal Nature Communications suggests that sea-level rise—one of the biggest consequences of global warming—will still be happening 300 years from now, even if humans stop emitting greenhouse gases before the end of the current century.

What's more, the longer it takes to start reducing global emissions, the higher those future sea levels will be.  The study suggests that for every additional five years it takes for emissions to peak and start falling—for instance, if emissions were to reach their maximum levels in the year 2030, as opposed to 2025—sea levels will rise an additional 8 inches by the year 2300.

"The Paris Agreement calls for emissions to peak as soon as possible," researcher Carl-Friedrich Schleussner of the Potsdam Institute for Climate Impact Research, one of the study's co-authors, said in a statement about the new paper.  "This might sound like a hollow phrase to some, but our results show that there are quantifiable consequences of delaying action."

The study emphasizes an important scientific concern about the progression of climate change—that its effects don't always occur immediately, or even quickly in some cases.  Even after humans stop emitting greenhouse gases into the atmosphere, global temperatures are expected to continue rising before they finally stabilize, potentially for decades.  And even after temperatures stop rising, other effects of climate change may continue to go on for hundreds of years.

Sea-level rise is one example.  Rising seas are caused by the combination of a number of different processes, including the warming of the ocean, which causes the water to expand in volume, and the melting of glaciers—particularly from the massive Greenland and Antarctic ice sheets.  Both of these processes may continue long after human-caused greenhouse gas emissions have come to a halt.

The melting of the ice sheets, in particular, is a process that may be difficult to stop once it's set in motion.  Even after global temperatures stabilize—and even if they stabilize within the 2-degree Celsius threshold outlined under the Paris climate agreement—the warming that occurs up to that point may destabilize the glaciers to an extent that continued ice loss becomes unstoppable far into the future.

In short, scientists generally believe that current greenhouse gas emissions have already committed the world to significant levels of sea-level rise for generations to come.  The question is how much—and to what extent different strategies for curbing emissions now may mitigate sea-level rise in the future.

Read more at Seas Will Rise for 300 Years

DHL Exec:  Tesla Semi Trucks to Pay for Themselves in 1.5 Years

Tesla Semi Truck Specs Event (Credit: Tesla) Click to Enlarge.
While Tesla CEO Elon Musk has already been quoted as promising that the payback period for choosing an all-electric Tesla Semi offering over a conventional diesel truck would be just a few years time, not everyone is willing to take his word on the matter.

With that in mind, it’s worth noting that an exec at DHL was recently quoted as saying that the payback period on the Tesla Semi — that is, the period of time that it takes to pay off the difference in initial costs as compared to a conventional diesel semi truck, before net savings kick in — would be under 1.5 years.  Again, after 1.5 years, that means the company is benefiting from net savings … while using cleaner trucks.

To give the exact words, the President of Transportation at DHL Supply Chain, Jim Monkmeyer, was quoted by Reuters as saying:  “We are estimating that we could have pay back within a year-and-a-half based on energy usage as well as lower maintenance cost.

“The maintenance savings can be enormous as well.  Just because the engines are much simpler in terms of the number of parts and the complexities of the parts.”

Read more at DHL Exec:  Tesla Semi Trucks to Pay for Themselves in 1.5 Years

Saturday, February 24, 2018

Saturday, Feb 24

Global surface temperature relative to 1880-1920 based on GISTEMP analysis (mostly NOAA data sources, as described by Hansen, J., R. Ruedy, M. Sato, and K. Lo, 2010: Global surface temperature change. Rev. Geophys., 48, RG4004.  We suggest in an upcoming paper that the temperature in 1940-45 is exaggerated because of data inhomogeneity in WW II. Linear-fit to temperature since 1970 yields present temperature of 1.06°C, which is perhaps our best estimate of warming since the preindustrial period.

Unwritten Paris Rules Dominate As Tense Year of Climate Diplomacy Begins in Japan

Diplomats meeting in Japan focused heavily on the contentious rules for the Paris deal, which are due to be set by the end of this year.


Diplomats meet in Tokyo this week (Photo Credit: Japan foreign ministry) Click to Enlarge.
A critical year of climate talks began this week at a meeting in Tokyo, Japan, which was dominated by the contentious and unwritten rulebook for the Paris Agreement.

Negotiators who struck the landmark deal in the French capital in 2015, left a great deal of the detail to be sorted out later.  The rules that govern the agreement are yet to be written and loom as a huge political fight to be resolved, or not, in Poland at the end of this year.

To ensure a successful outcome, negotiators have scheduled a packed year of talks.  In the first major meeting of 2018, 30 countries came together in Japan this week.

That included the US.  Despite the administration’s insistence they intend to leave the Paris deal as soon as legally possible (in 2020) the state department has continued to engage with the talks.

In a statement Japan’s ministry of foreign affairs said the discussions had been “candid” and “fruitful”.  France’s climate ambassador Brigitte Collet called them “intense”.

The informal meeting, which is co-chaired each year by Japan and Brazil, was used as an opportunity to set up talks for the year.  It ran over two days, ending Friday.  By far the longest session was devoted to the contentious Paris rulebook, which will dominate discussions in Katowice.  These rules will set how the commitments made to the deal are measured and verified.

Differences between some negotiating teams, especially the EU and China, over issues such as transparency have to date been irresolvable.

Read more at Unwritten Paris Rules Dominate As Tense Year of Climate Diplomacy Begins in Japan

Why Remote Antarctica Is So Important in a Warming World

Ever since the ancient Greeks speculated a continent must exist in the south polar regions to balance those in the north, Antarctica has been popularly described as remote and extreme.  Over the past two centuries, these factors have combined to create, in the human psyche, an almost mythical land – an idea reinforced by tales of heroism and adventure from the Edwardian golden age of “heroic exploration” and pioneers such as Robert Falcon Scott, Roald Amundsen, and Ernest Shackleton.

Recent research, however, is casting new light on the importance of the southernmost continent, overturning centuries of misunderstanding and highlighting the role of Antarctica in how our planet works and the role it may play in a future, warmer world.

What was once thought to be a largely unchanging mass of snow and ice is anything but.  Antarctica holds a staggering amount of water.  The three ice sheets that cover the continent contain around 70% of our planet’s fresh water, all of which we now know to be vulnerable to warming air and oceans.  If all the ice sheets were to melt, Antarctica would raise global sea levels by at least 56m (184 ft).

Where, when, and how quickly they might melt is a major focus of research.  No one is suggesting all the ice sheets will melt over the next century but, given their size, even small losses could have global repercussions.  Possible scenarios are deeply concerning:  in addition to rising sea levels, meltwater would slow down the world’s ocean circulation, while shifting wind belts may affect the climate in the southern hemisphere.

In 2014 NASA reported that several major Antarctic ice streams, which hold enough water to trigger the equivalent of a one-and-a-half meter sea level rise, are now irreversibly in retreat.  With more than 150m people exposed to the threat of sea level rise and sea levels now rising at a faster rate globally than any time in the past 3,000 years, these are sobering statistics for island nations and coastal cities worldwide.

Read more at Why Remote Antarctica Is So Important in a Warming World

Taming Turbulence Could Slash Global Energy Usage


Water main turbines (Credit: cleantechnica.com) Click to Enlarge.Pushing stuff through pipes is an important part of the global economy.  Whether it is air, water, oil, methane, or some other substance that contributes significantly to the great engine of commerce, much of it travels through pipes at some point.  And pushing it along takes a lot of energy.

Inside all those pipes — whether it is a transcontinental oil conduit or the ductwork that carries fresh air to the interior of commercial buildings — turbulence occurs.  That turbulence creates drag, which must be overcome by using more pumps and fans to move the stuff inside along.  According to a report by Bloomberg, fully 10% of all the electricity generated every year is consumed in the process of overcoming the effects of turbulence.  Imagine if all that energy could by put to use doing more useful things, like powering electric cars?

In 2015 German physicist Bjorn Hof and several colleagues were among the first to research precisely how turbulence occurs inside pipes and conduits.  Supported by research grants from the European Union, they gained a better understanding of how small eddies created at the interface between the fluid passing through a pipe and the walls of the pipe itself can aggregate into larger eddies.  In some cases, those eddies actually create counterflows that travel opposite to the primary direction of travel.  The amount of turbulence was found to correlate directly to the speed of the flow.

The findings from that research were published in the journal Nature but are unfortunately guarded by a pay wall.  The executive summary, however, is available and says in part, “At moderate flow speeds, turbulence is confined to localized patches; it is only at higher speeds that the entire flow becomes turbulent.  The origin of the different states encountered during this transition, the front dynamics of the turbulent regions and the transformation to full turbulence have yet to be explained.  By combining experiments, theory, and computer simulations, here we uncover a bifurcation scenario that explains the transformation to fully turbulent pipe flow and describe the front dynamics of the different states encountered in the process.”

Now, Hof, working with colleagues Jakob Kühnen and Baofang Song, has published new research that reveals novel ways they have found of controlling turbulence, chief among them installing rotors inside the pipes.  One might expect introducing new things into the flow might create more turbulence but the researchers found the opposite was true.  This latest report, published January 8 of this year, is not located behind a pay wall, so you can access it yourself if you enjoy reading turgid prose filled with scientific jargon.  Here is what the researchers have to say in their abstract.
We demonstrate for pipe flow that appropriate distortions to the velocity profile lead to a complete collapse of turbulence and subsequently friction losses are reduced by as much as 90%.  Counterintuitively, the return to laminar motion is accomplished by initially increasing turbulence intensities or by transiently amplifying wall shear.  Since neither the Reynolds number nor the shear stresses decrease (the latter often increase), these measures are not indicative of turbulence collapse.  Instead, an amplification mechanism measuring the interaction between eddies and the mean shear is found to set a threshold below which turbulence is suppressed beyond recovery.
If you are not a physicist, the salient point in that paragraph is a reduction in friction losses of up to 90%.  Less friction translates directly into less energy needed to move stuff through pipes.

Read more at Taming Turbulence Could Slash Global Energy Usage

Friday, February 23, 2018

Friday, Feb 23

Global surface temperature relative to 1880-1920 based on GISTEMP analysis (mostly NOAA data sources, as described by Hansen, J., R. Ruedy, M. Sato, and K. Lo, 2010: Global surface temperature change. Rev. Geophys., 48, RG4004.  We suggest in an upcoming paper that the temperature in 1940-45 is exaggerated because of data inhomogeneity in WW II. Linear-fit to temperature since 1970 yields present temperature of 1.06°C, which is perhaps our best estimate of warming since the preindustrial period.

Court Reverses 'Untethered' Suspension of BLM Methane Rule

A federal court reversed the Trump administration's plan to suspend restrictions on methane emissions from oil and gas development. (Credit: NOAA's Earth System Research Laboratory) Click to Enlarge.
A federal court dealt another major blow last night to the Trump administration's attempts to unwind Obama-era restrictions on methane emissions from the oil and gas industry.

The U.S. District Court for the Northern District of California ruled that the Bureau of Land Management did not justify its decision to postpone core provisions of its 2016 Methane and Waste Prevention Rule.

"The BLM's reasoning behind the Suspension Rule is untethered to evidence contradicting the reasons for implementing the Waste Prevention Rule, and so plaintiffs are likely to prevail on the merits," Judge William Orrick wrote in a late-night opinion.

"They have shown irreparable injury caused by the waste of publicly owned natural gas, increased air pollution and associated health impacts, and exacerbated climate impacts," he wrote.

Orrick issued a preliminary injunction requiring BLM to fully enforce the regulation.  The agency just released a broader proposal for a permanent rollback of most of the rule's provisions, but that plan won't be finalized until April, at the earliest.

The court's decision — the second time the court has blocked Interior Secretary Ryan Zinke's efforts to sideline the methane rule — is a tremendous victory for environmentalists and states that supported the Obama-era plan to reduce venting, flaring and leakage of the potent greenhouse gas on public and tribal lands.

California, New Mexico, and a coalition of environmental groups filed suit in December when the Trump administration suspended key provisions that required oil and gas drillers to craft waste minimization plans, use methane leak detection technology and cut back on flaring, among other measures.

They have defended the Obama measure as a necessary effort to avoid the waste of natural resources and reel in planet-warming emissions.

Read more at Court Reverses 'Untethered' Suspension of BLM Methane Rule