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   PoliticsThe Environmentalist Thread

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From: Ron12/22/2020 11:28:43 AM
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The Environmental Protection Agency is adopting new rules requiring water utilities to notify the public more quickly about possible lead contamination, the first major regulatory update of its kind in nearly 30 years.

The measure signed Monday evening by EPA Administrator Andrew Wheeler will require utilities to alert customers of high lead concentrations within 24 hours of detection—rather than within 30 days—of learning the results of lead tests.

Water utilities will also be required for the first time to test for lead in the water supplies of schools and child-care centers, and to replace their lead-pipe systems any time their customers replace the lead pipes they own in their homes and businesses.

Utilities that find high lead levels in their water will also get more time to replace their lead pipes, a measure that drew opposition from environmental groups.

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From: left-over man12/30/2020 2:01:27 PM
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Using urine to heat homes

Waste not, want not

Jan 2nd 2021

Urine, though distained by modern society, was once surprisingly useful stuff. Street-facing laundries in ancient Rome had pissoirs attached to them, to encourage passers-by in need of relief to provide, free of charge, a raw material which was then fermented into a degreasing agent. Urine also found employment as a mordant, to assist in the dying of cloth—Scottish tweed was once notorious for smelling of the stuff when it got wet. And urine was, too, a source of potassium nitrate, one of the ingredients of gunpowder.

Now, Chen Wei-Shan of Wageningen University, in the Netherlands, thinks he has found yet another use for urine—and one relevant to today’s needs rather than yesterday’s. He plans to employ it to create heat without fire from waste wood.

Burning wood is a good source of heat and it can be seen as sound from the point of view of greenhouse gases. That is because the carbon dioxide released into the atmosphere came thence in the first place, and would return there anyway if the wood in question were simply allowed to rot. But wood fires also bring environmental disbenefits, for they give off sulphur dioxide, carbon monoxide and other noxious gases along with that CO2.

Researchers have therefore been looking for ways to release wood’s latent heat by composting rather than combustion. Unfortunately, unlike other stuff that is routinely composted (dung and waste food, for example) wood does not, by itself, contain a wide enough range of nutrients to sustain the relevant micro-organisms. To digest it, these bugs need dietary supplements. And those—things like ammonium chloride—are too expensive for everyday use.

But urine is cheap—or would be, if routine ways of collecting it existed. And it contains large quantities of nitrogen and potassium (as its use in gunpowder demonstrates) and also of phosphorus (an element that was, as it happens, discovered by an alchemist trying to extract gold from urine). These are all nutrients which composting bugs need to thrive. So, as he writes in acs Sustainable Chemistry & Engineering, Dr Chen decided to give it a go.

To this end, he and his colleagues added urine to kiln-dried ash wood and composted the result in glass bottles. Some of this urine was actually a synthetic version, so that its composition was known precisely. The rest was donated by a 28-year-old man who had been medication-free during the previous two years. Both the artificial and the natural urine were diluted, to various degrees, during the process of testing.

The team found that oxygen consumption, wood consumption and heat production all rose rapidly in the jars during the experiment’s first week. Once things had settled, though, it was clear natural urine had something going for it which synthetic urine did not. The best synthetic-urine dilution (one part in five parts of water) resulted in a 13% loss of mass of wood after 40 days. The best natural urine dilution (one part in 8.5) brought about a 20% loss.

Why natural urine is more effective than the artificial stuff at the task Dr Chen set it remains unclear. He speculates that it is because natural urine is slightly more acidic, and that this matters to some of the relevant bugs. Which ones in particular, however, he has yet to work out.

Previous experiments suggest that compost-heaps of wood fed suitable nutrients can sustain internal temperatures of 40-55°C for long periods. That is high enough to be useful for heating buildings and, with a bit of a boost, perhaps for providing hot water as well. To commercialise the idea would mean designing a suitable reactor and heat exchanger, but the waste-wood fuel would be cheap. How you would go about gathering the necessary urine in bulk, given the expense of installing a network of suitably dedicated collection points, is not clear. But governments contemplating doing so might be heartened by the fact that, in Rome, the Emperor Vespasian slapped a lucrative tax on the city’s urinals—something once commemorated in France by the slang name for an old-fashioned pissoir: “une vespasienne”.

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From: left-over man1/13/2021 1:19:34 PM
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Transport & Environment:

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From: Wharf Rat1/18/2021 11:49:47 AM
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2020 Hindsight
Filed under: Arctic and Antarctic Climate Science El Nino In the News Instrumental Record — gavin @ 15 January 2021

Yesterday was the day that NASA, NOAA, the Hadley Centre and Berkeley Earth delivered their final assessments for temperatures in Dec 2020, and thus their annual summaries. The headline results have received a fair bit of attention in the media ( NYT, WaPo, BBC, The Guardian etc.) and the conclusion that 2020 was pretty much tied with 2016 for the warmest year in the instrumental record is robust.

There is some more background here:
[Note we will work on the model-observation comparison page to add the 2020 data point to the graphs, and update the datasets to their latest versions, but nothing dramatic will change – the latest observations remain pretty much in line with what models predicted. ]

But there are a few issues that readers here might appreciate that goes beyond what usually gets reported.

How does ENSO affect annual temperatures?

If you do a regression of the year-to-year variations in global temperature, you’ll find that the highest correlations are with the spring ENSO index (the February-March average to be specific, but almost any index from the winter/spring works equally well). Using that regression, you can estimate that the 2016 El Niño added 0.11ºC to the global temperatures in that year, and that we would have expected a much smaller 0.03ºC for 2020 (given the slight ENSO positive conditions early in the year. However, in the map of 2020 anomalies, the tropical Pacific looks to be (on average) slightly negative in phase, driven by the emerging La Niña event this fall/winter.

That suggests that we could usefully build a more complex connection between the global mean and ENSO – either with more predictors (say Feb/Mar but also Oct/Nov?) or by using a lagged model on the monthly anomalies. I’d be interested in any results people get and if it changes the ENSO-corrected annual timeseries substantially.

What are the uncertainties in these estimates?

There have been some real advances over the years in how we think about the uncertainty in these estimates. The work with the HadCRUT ensemble, the Berkeley Earth statistical model and the work in Lenssen et al (2019) for GISTEMP, have all gone way beyond the old style of estimates from a decade ago. But there are some aspects of the uncertainty that remain hard to analyse – for instance, it isn’t quite right to assume the margin for one year is independent of the margin for the next year – since they will have been similarly affected by the station network at these times or the homogeneity adjustments which will be similar for both. So while the probabilities for record years given here are reasonable, they may be due for a (minor) revision in the near future.

The perennial issue of the Arctic coverage is now almost done with. HadCRUT5 now extrapolates into the Arctic as well, and the upcoming revisions to the NOAA methodology (Vose et al, in press) do the same as well as ingesting Arctic buoy data. This will effectively eliminate the cool bias that resulted from only partially weighting the Arctic changes and reduce the difference between the products to almost negligible values (except where the HadSST and ERSST products differ).

Structural uncertainty in satellite records

The main focus of these annual announcements is on the in situ land station/ocean buoy/ship data compilations, but as many will know there are a number of satellite products of related variables that offer an independent view of recent trends. Specifically, there are the MSU TLT products (from RSS and UAH) and the AIRS instrument data (flying on NASA’s Aqua satellite since 2003). These products are the combination of raw data (brightness temperatures in the microwave band and IR band respectively) together with complex retrieval algorithms which correct for the presence of clouds or surface emissivity or atmospheric distortions of various sorts. As such, the retrievals are often updated as improved methods are found, or calibration targets refined, or corrections found.

RSS retrievals are on version 4, UAH on version 6, and the AIRS retrievals have just moved to version 7. At each new version, the whole record is reprocessed and while the new results are often highly correlated with the older versions, trends can sometimes be quite different. This ‘structural’ uncertainty in the long term is often neglected when comparing these observations with other products or model output. Nonetheless, it is a significant issue. To illustrate this, note the difference between UAH and RSS below – highly correlated year-to-year, but radically different trends (and therefore interpretations) over the length of the record. For reference, the GISTEMP and HadCRUT5 products can barely be distinguished.

Similarly, the two versions of the AIRS product (v6 (red) and v7 (pink)) are well-correlated from year to year, but diverge notably in the early years of that record (2003-2006). The point being that structural issues in satellite products can have much larger impacts than structural issues in the surface station products (even if you consider the polar problem). Only drawing conclusions that are robust to these issues seems sensible.

And one pet peeve.

It seems I need to say this every year, but attempts to give a high-precision absolute temperature value for a single year are scientifically invalid. Our knowledge of the absolute global mean temperature has an uncertainty of about 0.5ºC, while the uncertainty in the annual mean anomaly is more like 0.05ºC. You don’t get an accurate number by adding an inaccurate one to an accurate one. What happens when this occurs is that updates in the absolute global mean (because of a new reanalysis, better observational data, etc.) can dwarf the year-to-year anomaly and you end up with an ‘absolute’ number from 24 years ago weirdly being larger than an absolute number today:

One example is sufficient to demonstrate the problem. In 1997, the NOAA state of the climate summary stated that the global average temperature was 62.45ºF (16.92ºC). The page now has a caveat added about the issue of the baseline, but a casual comparison to the statement in 2016 stating that the record-breaking year had a mean temperature of 58.69ºF (14.83ºC) could be mightily confusing. In reality, 2016 was warmer than 1997 by about 0.5ºC!

Just don’t do it.

    N.J.L. Lenssen, G.A. Schmidt, J.E. Hansen, M.J. Menne, A. Persin, R. Ruedy, and D. Zyss, "Improvements in the GISTEMP Uncertainty Model", Journal of Geophysical Research: Atmospheres, vol. 124, pp. 6307-6326, 2019.

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From: left-over man1/19/2021 1:35:05 PM
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Green Wave:

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From: Wharf Rat1/23/2021 7:53:48 PM
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Americans Are Moving To Escape Climate Impacts. Towns Expect More To Come
January 22, 20215:00 AM ET


Doug and Judith Saum moved to New Hampshire from Reno, Nev., to escape the health effects of worsening wildfire smoke.

Annie Ropeik/NHPR

The impacts of climate change could prompt millions of Americans to relocate in coming decades, moving inland away from rising seas, or north to escape rising temperatures.

Judith and Doug Saum have moved already, recently leaving their home outside Reno, Nev.

"It was with a view of the Sierra [Nevada Mountains] that was just to die for," Judith says. "We had a lot of friends, musician friends, we'd get together and play music with them often. It wasn't easy to leave all that."

The Saums had long thought about retiring to Colorado or Montana to be near family. But as they started making those plans several years ago, they were also noticing a new problem: Wildfire season was getting worse and longer in their part of the country, fueled by climate change.

"For me, it was unbearable because I was so sensitive to the smoke that I start to swell up," says Judith. "I get sinus infections, and going outside was intolerable."

The Saums settled on northern New England and a house in the rural town of Rumney at the foot of New Hampshire's White Mountains.

Doug Saum says they call themselves climate migrants.

"We had the idea ... not necessarily that we were going to a place that would be forever untouched by climate change, but that we were getting out of a bad climate situation that was only likely to get worse," he says.

For others, climate-related hazards will be just one reason to move. Bess Samuel says her family has wanted to leave Huntsville, Ala., for a less conservative place for a while — and rising temperatures and power bills could seal the deal.

"I feel like I have to be realistic — this is as good as it's going to get for a while," Samuel says. "We keep hearing these things ... it's the hottest summer and it's the hottest summer and that trend doesn't seem to be reversing."

Inland parts of northern New England expect people to migrate from coastal towns like Hampton, N.H., where high-tide flooding is increasing because of rising seas.

Dan Tuohy/NHPR

Jola Ajibade studies climate migration as an assistant professor at Portland State University in Oregon.

"Impermanence might be the new normal for many of us," she says. "The idea that you have to live in one place forever, I think people have to forget that... And I think people who have been able to do that historically, I think it's a privilege that they should celebrate."

But she says all this moving around can make people resilient. And if the places that will receive these new residents can be resilient and flexible, too, the communities might just benefit from it.

Pandemic influx shows the need to plan

"When we've talked about climate migration, it usually comes up in the context of the jobs that we just can't fill," says Sarah Marchant, the community development director in Nashua, N.H.

Nashua has already seen its Puerto Rican population grow after Hurricane Maria hit the island, and it expects more climate migrants from Boston and other nearby coastal areas.

"I think the city is well-positioned with the infrastructure we already have, and our location that is very desirable," Marchant says. "We are an hour from Boston, a little over an hour from the Seacoast and two hours to the mountains, and so we are connected to everything."

By some measures, Nashua's region could be an ideal climate haven. It's getting warmer, but it doesn't face the existential threats of, say, Florida from hurricanes and flooding or California from wildfires and smoke. Northern New England is also one of the oldest and whitest parts of the country and has struggled with population loss.

But it's hard to predict the scale and timing of climate migration. And an influx of newcomers during the current pandemic is showing just how disruptive unplanned growth can be.

"An increase in traffic, people getting evicted, a lack of hospital beds because there's more people – these are the kinds of things that create tension," says Anna Marandi, a senior climate specialist with the National League of Cities. "When the systems aren't set up properly in advance to hold more people, then the existing population can get resentful."

So Sarah Marchant says Nashua is keeping migration and other climate impacts in mind while tackling existing problems with affordable housing and overstretched infrastructure. The idea is "to ensure that what we are building is sustainable," she says, and to "be smarter about what we do have."

Whether or not the climate migrants come, she says Nashua is making improvements that will benefit everyone.

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From: Wharf Rat2/6/2021 9:09:52 AM
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Deadlines loom for Capitol Hill action on Trump-era climate issues
Posted on 5 February 2021 by Guest Author
This commentary, authored by Gary Yohe, Henry Jacoby, Richard Richels and Benjamin Santer, was originally published on the Yale Climate Connections website on Jan 26, 2021. It is reposted below in its entirety. Click here to access the original article posted on Yale Climate Connections.

Deadlines loom for Capitol Hill action on Trump-era climate issuesAs with the new Biden administration, Congress too faces a deadline for acting on Trump-era 'eleventh-hour' regulations.

by Gary Yohe, Henry Jacoby, Richard Richels and Benjamin Santer

Much ink has been spilled in recent weeks, figuratively speaking, on what the Biden/Harris administration’s first 100 days in office reveal about its making climate change a top priority. Those words have flowed both at this site and many other venues.

The Washington Post’s January 22 posting of “ Tracking Biden’s environmental actions” is notable. Written by Post Pulitzer Prize winners Juliet Eilperin and Brady Dennis, with graphics editing by John Muyskens, the piece compiles Trump administration environmental, conservation, and energy regulations and policies that the Biden team hopes to overturn or “unwind.”

“Biden can overturn some of them with a stroke of a pen,” they write. “Others will take years to undo, and some may never be reversed.”

Listing 64 air quality and greenhouse gas initiatives, they count one (stepping back into the Paris Climate Agreement) as having been overturned and another 21 as being “easy” to reverse. They score another 27 Trump actions as “medium” – requiring rewriting a regulation or pursuing a successful court action; and 15 as “difficult” – requiring lengthy rule-making process, legislation, or involved court action.

Clock is running for action on eleventh-hour rules

Along with the quickly-ticking clock in the White House on the administration’s first 100 days, let’s not lose sight of another clock that is also running on Capitol Hill. It is not necessarily identical, second-by-second, but just as relentless.

As is the case with so many others who have spent years working to bring climate change to the fore as a critical national and international issue, we are pleased with the day-one Biden Executive Order to re-enter the Paris Climate Agreement. Fortunately, given the din of opposition from the usual voices on Capitol Hill, that action does not require congressional approval. The U.S. will be officially back in on February 19th – and the global community can continue to welcome our return.

It’s no surprise that the fawning Senate majority of the 116th Congress did not exercise its right under the Congressional Review Act (CRA) to un-do damaging Trump rules. But even with its razor-thin 50/50 split in the new Senate, the new 117th Congress is positioned to do so, without fear of having to overcome the 60-vote filibuster threshold. There is now, at least and at last, an opportunity during its first 60 legislative workdays for the Congress to conduct serious oversight of some of the especially offensive and glaring rules finalized in the waning days of the Trump administration and, if it chooses, send nullifying legislation to the new President for signing.

A few especially egregious examples were published in the Federal Register literally at the 11th hour:

A January 6, 2021, rule that EPA “give greater consideration to studies where the underlying response data” – frequently involving confidential human health issues protected by HIPAA law being made publicly available. That would knee-cap important health-based rulemaking on many toxic air pollutants and other contaminants as well as the mental health risks from climate change.A January 7, 2021, EPA rule on the threshold for “significant pollution contributions” that would end application of the Clean Air Act to many non-electric power plants that are sources of important greenhouse gases.A January 13, 2021, EPA rule that piggy-backed onto the January 7 rule to bar future greenhouse gas regulations from applying to oil refineries, manufacturing, plants, and other facilities.Appropriate Senate and House committees of jurisdiction now owe it to their air-breathing constituents to seek expert analyses as they review these and other Trump-era health and safety rules before the clock runs out on them for such oversight; and, where appropriate, to take action.

In some cases, nullification under the Congressional Review Act may be most appropriate and most expeditious. In some other cases, Biden administration executive action may be more appropriate. In still others, judicial action may be best.

The Trump administration itself, like the 115th Congress taking office in January 2017, proved to be prodigious and, it must be acknowledged, an effective practitioner of the using the Congressional Review Act. Its actions nullified Obama/Biden administration policies on climate change and other environmental and public health issues. That law, still untested in the courts, has been used only 17 times since it was enacted as part of the 1996 Newt Gingrich-inspired “Contract with America”; 16 of those came soon after the Trump administration took office.

There’s a saying familiar to us all: “What’s good for the goose is good for the gander.” It is especially apropos when the resulting actions enjoy bipartisan support from the public at large. This is a time when legislators should listen, and closely, to what their constituents are saying and expecting them to do.

Gary Yohe is the Huffington Foundation Professor of Economics and Environmental Studies, Emeritus, at Wesleyan University in Connecticut. He served as convening lead author for multiple chapters and the Synthesis Report for the IPCC from 1990 through 2014 and was vice-chair of the Third U.S. National Climate Assessment.

Henry Jacoby is the William F. Pounds Professor of Management, Emeritus, in the MIT Sloan School of Management and former co-director of the MIT Joint Program on the Science and Policy of Global Change, which is focused on the integration of the natural and social sciences and policy analysis on threats to the global climate.

Richard Richels directed climate change research at the Electric Power Research Institute (EPRI). He served as lead author for multiple chapters of the IPCC in the areas of mitigation, impacts, and adaptation from 1992 through 2014. He also served on the National Assessment Synthesis Team for the first U.S. National Climate Assessment.

Ben Santer served as convening lead author of the climate change detection and attribution chapter of the IPCC’s Second Assessment Report and has contributed to all five IPCC assessments.

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To: Wharf Rat who wrote (36528)2/6/2021 5:32:24 PM
From: Land Shark
of 36567
NASA GISS webpage has quickly changed it's focus now that the criminal FarRump regime is gone.

They now make articles like this the forefront. Censorship begone!

A Destructive Abundance
By Kasha Patel, NASA Earth Observatory — December 10, 2020
The 2020 Atlantic hurricane season will go down in history as a season of superlatives: the most named storms observed in a year (30); the most storms to make landfall in the continental United States (12); the most to hit Louisiana (5); and the most storms to form in September (10). The 2020 season was supercharged, and not just in the raw numbers.

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To: Land Shark who wrote (36529)2/16/2021 12:46:19 PM
From: left-over man
of 36567
Production, use, and fate of all plastics ever made


Plastics have outgrown most man-made materials and have long been under environmental scrutiny. However, robust global information, particularly about their end-of-life fate, is lacking. By identifying and synthesizing dispersed data on production, use, and end-of-life management of polymer resins, synthetic fibers, and additives, we present the first global analysis of all mass-produced plastics ever manufactured. We estimate that 8300 million metric tons (Mt) as of virgin plastics have been produced to date. As of 2015, approximately 6300 Mt of plastic waste had been generated, around 9% of which had been recycled, 12% was incinerated, and 79% was accumulated in landfills or the natural environment. If current production and waste management trends continue, roughly 12,000 Mt of plastic waste will be in landfills or in the natural environment by 2050.


A world without plastics, or synthetic organic polymers, seems unimaginable today, yet their large-scale production and use only dates back to ~1950. Although the first synthetic plastics, such as Bakelite, appeared in the early 20th century, widespread use of plastics outside of the military did not occur until after World War II. The ensuing rapid growth in plastics production is extraordinary, surpassing most other man-made materials. Notable exceptions are materials that are used extensively in the construction sector, such as steel and cement ( 1, 2).

Instead, plastics’ largest market is packaging, an application whose growth was accelerated by a global shift from reusable to single-use containers. As a result, the share of plastics in municipal solid waste (by mass) increased from less than 1% in 1960 to more than 10% by 2005 in middle- and high-income countries ( 3). At the same time, global solid waste generation, which is strongly correlated with gross national income per capita, has grown steadily over the past five decades ( 4, 5).

The vast majority of monomers used to make plastics, such as ethylene and propylene, are derived from fossil hydrocarbons. None of the commonly used plastics are biodegradable. As a result, they accumulate, rather than decompose, in landfills or the natural environment ( 6). The only way to permanently eliminate plastic waste is by destructive thermal treatment, such as combustion or pyrolysis. Thus, near-permanent contamination of the natural environment with plastic waste is a growing concern. Plastic debris has been found in all major ocean basins ( 6), with an estimated 4 to 12 million metric tons (Mt) of plastic waste generated on land entering the marine environment in 2010 alone ( 3). Contamination of freshwater systems and terrestrial habitats is also increasingly reported ( 79), as is environmental contamination with synthetic fibers ( 9, 10). Plastic waste is now so ubiquitous in the environment that it has been suggested as a geological indicator of the proposed Anthropocene era ( 11).

We present the first global analysis of all mass-produced plastics ever made by developing and combining global data on production, use, and end-of-life fate of polymer resins, synthetic fibers, and additives into a comprehensive material flow model. The analysis includes thermoplastics, thermosets, polyurethanes (PURs), elastomers, coatings, and sealants but focuses on the most prevalent resins and fibers: high-density polyethylene (PE), low-density and linear low-density PE, polypropylene (PP), polystyrene (PS), polyvinylchloride (PVC), polyethylene terephthalate (PET), and PUR resins; and polyester, polyamide, and acrylic (PP&A) fibers. The pure polymer is mixed with additives to enhance the properties of the material.


Global production of resins and fibers increased from 2 Mt in 1950 to 380 Mt in 2015, a compound annual growth rate (CAGR) of 8.4% (table S1), roughly 2.5 times the CAGR of the global gross domestic product during that period ( 12, 13). The total amount of resins and fibers manufactured from 1950 through 2015 is 7800 Mt. Half of this—3900 Mt—was produced in just the past 13 years. Today, China alone accounts for 28% of global resin and 68% of global PP&A fiber production ( 1315). Bio-based or biodegradable plastics currently have a global production capacity of only 4 Mt and are excluded from this analysis ( 16).

We compiled production statistics for resins, fibers, and additives from a variety of industry sources and synthesized them according to type and consuming sector (table S2 and figs. S1 and S2) ( 1224). Data on fiber and additives production are not readily available and have typically been omitted until now. On average, we find that nonfiber plastics contain 93% polymer resin and 7% additives by mass. When including additives in the calculation, the amount of nonfiber plastics (henceforth defined as resins plus additives) manufactured since 1950 increases to 7300 Mt. PP&A fibers add another 1000 Mt. Plasticizers, fillers, and flame retardants account for about three quarters of all additives (table S3). The largest groups in total nonfiber plastics production are PE (36%), PP (21%), and PVC (12%), followed by PET, PUR, and PS (<10% each). Polyester, most of which is PET, accounts for 70% of all PP&A fiber production. Together, these seven groups account for 92% of all plastics ever made. Approximately 42% of all nonfiber plastics have been used for packaging, which is predominantly composed of PE, PP, and PET. The building and construction sector, which has used 69% of all PVC, is the next largest consuming sector, using 19% of all nonfiber plastics (table S2).

We combined plastic production data with product lifetime distributions for eight different industrial use sectors, or product categories, to model how long plastics are in use before they reach the end of their useful lifetimes and are discarded ( 22, 2529). We assumed log-normal distributions with means ranging from less than 1 year, for packaging, to decades, for building and construction ( Fig. 1). This is a commonly used modeling approach to estimating waste generation for specific materials ( 22, 25, 26). A more direct way to measure plastic waste generation is to combine solid waste generation data with waste characterization information, as in the study of Jambeck et al. ( 3). However, for many countries, these data are not available in the detail and quality required for the present analysis.

We estimate that in 2015, 407 Mt of primary plastics (plastics manufactured from virgin materials) entered the use phase, whereas 302 Mt left it. Thus, in 2015, 105 Mt were added to the in-use stock. For comparison, we estimate that plastic waste generation in 2010 was 274 Mt, which is equal to the independently derived estimate of 275 Mt by Jambeck et al. ( 3). The different product lifetimes lead to a substantial shift in industrial use sector and polymer type between plastics entering and leaving use in any given year (tables S4 and S5 and figs. S1 to S4). Most of the packaging plastics leave use the same year they are produced, whereas construction plastics leaving use were produced decades earlier, when production quantities were much lower. For example, in 2015, 42% of primary nonfiber plastics produced (146 Mt) entered use as packaging and 19% (65 Mt) as construction, whereas nonfiber plastic waste leaving use was 54% packaging (141 Mt) and only 5% construction (12 Mt). Similarly, in 2015, PVC accounted for 11% of nonfiber plastics production (38 Mt) and only 6% of nonfiber plastic waste generation (16 Mt).

By the end of 2015, all plastic waste ever generated from primary plastics had reached 5800 Mt, 700 Mt of which were PP&A fibers. There are essentially three different fates for plastic waste. First, it can be recycled or reprocessed into a secondary material ( 22, 26). Recycling delays, rather than avoids, final disposal. It reduces future plastic waste generation only if it displaces primary plastic production ( 30); however, because of its counterfactual nature, this displacement is extremely difficult to establish ( 31). Furthermore, contamination and the mixing of polymer types generate secondary plastics of limited or low technical and economic value. Second, plastics can be destroyed thermally. Although there are emerging technologies, such as pyrolysis, which extracts fuel from plastic waste, to date, virtually all thermal destruction has been by incineration, with or without energy recovery. The environmental and health impacts of waste incinerators strongly depend on emission control technology, as well as incinerator design and operation. Finally, plastics can be discarded and either contained in a managed system, such as sanitary landfills, or left uncontained in open dumps or in the natural environment.

We estimate that 2500 Mt of plastics—or 30% of all plastics ever produced—are currently in use. Between 1950 and 2015, cumulative waste generation of primary and secondary (recycled) plastic waste amounted to 6300 Mt. Of this, approximately 800 Mt (12%) of plastics have been incinerated and 600 Mt (9%) have been recycled, only 10% of which have been recycled more than once. Around 4900 Mt—60% of all plastics ever produced—were discarded and are accumulating in landfills or in the natural environment ( Fig. 2). Of this, 600 Mt were PP&A fibers. None of the mass-produced plastics biodegrade in any meaningful way; however, sunlight weakens the materials, causing fragmentation into particles known to reach millimeters or micrometers in size ( 32). Research into the environmental impacts of these “microplastics” in marine and freshwater environments has accelerated in recent years ( 33), but little is known about the impacts of plastic waste in land-based ecosystems.

Before 1980, plastic recycling and incineration were negligible. Since then, only nonfiber plastics have been subject to significant recycling efforts. The following results apply to nonfiber plastic only: Global recycling and incineration rates have slowly increased to account for 18 and 24%, respectively, of nonfiber plastic waste generated in 2014 (figs. S5 and S6). On the basis of limited available data, the highest recycling rates in 2014 were in Europe (30%) and China (25%), whereas in the United States, plastic recycling has remained steady at 9% since 2012 ( 12, 13, 3436). In Europe and China, incineration rates have increased over time to reach 40 and 30%, respectively, in 2014 ( 13, 35). However, in the United States, nonfiber plastics incineration peaked at 21% in 1995 before decreasing to 16% in 2014 as recycling rates increased, with discard rates remaining constant at 75% during that time period ( 34). Waste management information for 52 other countries suggests that in 2014, the rest of the world had recycling and incineration rates similar to those of the United States ( 37). To date, end-of-life textiles (fiber products) do not experience significant recycling rates and are thus incinerated or discarded together with other solid waste.

Primary plastics production data describe a robust time trend throughout its entire history. If production were to continue on this curve, humankind will have produced 26,000 Mt of resins, 6000 Mt of PP&A fibers, and 2000 Mt of additives by the end of 2050. Assuming consistent use patterns and projecting current global waste management trends to 2050 (fig. S7), 9000 Mt of plastic waste will have been recycled, 12,000 Mt incinerated, and 12,000 Mt discarded in landfills or the natural environment.

Any material flow analysis of this kind requires multiple assumptions or simplifications, which are listed in Materials and Methods, and is subject to considerable uncertainty; as such, all cumulative results are rounded to the nearest 100 Mt. The largest sources of uncertainty are the lifetime distributions of the product categories and the plastic incineration and recycling rates outside of Europe and the United States. Increasing/decreasing the mean lifetimes of all product categories by 1 SD changes the cumulative primary plastic waste generation (for 1950 to 2015) from 5900 to 4600/6200 Mt or by -4/+5%. Increasing/decreasing current global incineration and recycling rates by 5%, and adjusting the time trends accordingly, changes the cumulative discarded plastic waste from 4900 (for 1950 to 2015) to 4500/5200 Mt or by -8/+6%.

The growth of plastics production in the past 65 years has substantially outpaced any other manufactured material. The same properties that make plastics so versatile in innumerable applications—durability and resistance to degradation—make these materials difficult or impossible for nature to assimilate. Thus, without a well-designed and tailor-made management strategy for end-of-life plastics, humans are conducting a singular uncontrolled experiment on a global scale, in which billions of metric tons of material will accumulate across all major terrestrial and aquatic ecosystems on the planet. The relative advantages and disadvantages of dematerialization, substitution, reuse, material recycling, waste-to-energy, and conversion technologies must be carefully considered to design the best solutions to the environmental challenges posed by the enormous and sustained global growth in plastics production and use.

Plastic production

The starting point of the plastic production model is global annual pure polymer (resin) production data from 1950 to 2015, published by the Plastics Europe Market Research Group, and global annual fiber production data from 1970 to 2015 published by The Fiber Year and Tecnon OrbiChem (table S1). The resin data closely follow a second-order polynomial time trend, which generated a fit of R2 = 0.9968. The fiber data closely follow a third-order polynomial time trend, which generated a fit of R2 = 0.9934. Global breakdowns of total production by polymer type and industrial use sector were derived from annual market and polymer data for North America, Europe, China, and India (table S2) ( 12, 13, 1924). U.S. and European data are available for 2002 to 2014. Polymer type and industrial use sector breakdowns of polymer production are similar across countries and regions.

Global additives production data, which are not publicly available, were acquired from market research companies and cross-checked for consistency (table S3) ( 17, 18). Additives data are available for 2000 to 2014. Polymer type and industrial use sector breakdowns of polymer production and the additives to polymer fraction were both stable over the time period for which data are available and thus assumed constant throughout the modeling period of 1950–2015. Any errors in the early decades were mitigated by the lower production rates in those years. Additives data were organized by additive type and industrial use sector and integrated with the polymer data. Pi (t) denotes the amount of primary plastics (that is, polymers plus additives) produced in year t and used in sector i (fig. S1).

Plastic waste generation and fatePlastics use was characterized by discretized log-normal distributions, LTDi (j), which denotes the fraction of plastics in industrial use sector i used for j years ( Fig. 1). Mean values and SDs were gathered from published literature (table S4) ( 22, 2529). Product lifetimes may vary significantly across economies and also across demographic groups, which is why distributions were used and sensitivity analysis was conducted with regard to mean product lifetimes. The total amount of primary plastic waste generated in year t was calculated as PW (t) = (figs. S3 and S4). Secondary plastic waste generated in year t was calculated as the fraction of total plastic waste that was recycled k years ago, SW (t) = [PW (t - k) + SW (t - k)][RR (t - k)], where k is the average use time of secondary plastics and RR (t - k) is the global recycling rate in year t - k. Amounts of plastic waste discarded and incinerated are calculated as DW(t) = [PW(t) + SW(t) · DR(t) and IW(t) = [PW(t) + SW(t)] · IR(t), with DR(t) and IR(t) being the global discard and incineration rates in year t (fig. S5). Cumulative values at time T were calculated as the sum over all T - 1950 years of plastics mass production. Examples are cumulative primary production and cumulative primary plastic waste generation,

Recycling, incineration, and discard ratesTime series for resin, that is, nonfiber recycling, incineration, and discard rates were collected separately for four world regions: the United States, the EU-28 plus Norway and Switzerland, China, and the rest of the world. Detailed and comprehensive solid waste management data for the United States were published by the U.S. Environmental Protection Agency dating back to 1960 (table S7) ( 34). European data were from several reports by PlasticsEurope, which collectively cover 1996 to 2014 ( 12, 13, 38). Chinese data were synthesized and reconciled from the English version of the China Statistical Yearbook, translations of Chinese publications and government reports, and additional waste management literature ( 35, 36, 3941). Waste management for the rest of the world was based on World Bank data ( 37). Time series for global recycling, incineration, and discard rates (fig. S5) were derived by adding the rates of the four regions weighted by their relative contribution to global plastic waste generation. In many world regions, waste management data were sparse and of poor quality. For this reason, sensitivity analysis with regard to waste management rates was conducted.

The resulting global nonfiber recycling rate increased at a constant 0.7% per annum (p.a.) between 1990 and 2014. If this linear trend is assumed to continue, the global recycling rate would reach 44% in 2050. The global nonfiber incineration rate has grown more unevenly but, on average, increased 0.7% p.a. between 1980 and 2014. Assuming an annual increase of 0.7% between 2014 and 2050 yielded a global incineration rate of 50% by 2050. With those two assumptions, global discard rate would decrease from 58% in 2014 to 6% in 2050 (fig. S7). The dashed lines in Fig. 3are based on those assumptions and therefore simply forward projections of historical global trends and should not be mistaken for a prediction or forecast. There is currently no significant recycling of synthetic fibers. It was thus assumed that end-of-life textiles are incinerated and discarded together with all other municipal solid waste.

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From: left-over man2/16/2021 12:49:05 PM
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Unlike currently used plastics recycling processes, which are primarily thermo-mechanical, the recycling process developed by CARBIOS is based on highly specific biological tools: Enzymes!

This new approach enables the specific de-polymerization of a single polymer (e.g., PET) contained in the various plastics to be recycled. At the end of this stage, the monomer or monomers resulting from the de-polymerization process will be purified, with the objective to re-polymerize them, thus enabling a recycling process to infinity. Eventually, the plastic residues not degraded during the first stage will be de-polymerized in the same way in a second stage by applying a different enzyme that will de-polymerize other polymers in the same way as in the first stage.

For the first time in the history of the plastics industry, it is possible to recycle plastic waste to infinity to create new plastic materials and to accomplish this without a sophisticated sorting process.

CARBIOS’ recycling bioprocesses for plastics provide the means to:

Recycle plastics to infinity by returning to the original monomers which can be used in all applications in which the original material was used;Recover in the recycled materials the same level of performance displayed by the original materials.Among plastic waste, CARBIOS is particularly interested in polyesters (PET, PLA, etc.) and polyamides. These polymers have chains of monomers that are easily identifiable by the enzymes, and are thus easier to de-polymerize.

Therefore, this technology particularly targets the global market of plastic bottles (water, milk, sodas, cosmetics…), packaging and films.

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