Sunday, December 31, 2023

Our Woodlands Need Our Help

a finished section 

I am embarking on the fifth year of my woodland restoration project. My house sits on a bit over 10 acres, about three of them lawn and ornamental gardens. The remaining seven acres is woodland, and much of the woodland is part of the “resource protected area,” RPA, of the Chesapeake Bay. 

When we first moved here we did not worry about dead trees, as it was all part of the natural process of renewal. A healthy forest has living trees functioning as part of a balanced and self replacing ecosystem that is a complex mix of trees, understory shrubs and groundcover. In a healthy woodland the process of natural succession occurs over time. Small saplings develop and will become the next generation of trees as the older ones die out. Benign neglect had been my rule for managing the RPA that protects the stream.  

However, about a decade ago, I noticed that something had gone seriously wrong with the forest. The woodland was being destroyed by invasive insects, invasive vines and an explosion of deer and wildlife consuming the native understory. Though I have seen them munch the kibble we put out for the cats dumped in our woods, deer prefer to eat native plants. They devour the saplings of the native  trees, but pretty much leave the autumn olive and other invasives alone. When a gap appears in the canopy, there aren’t young trees in the understory waiting for their chance to grow in the sun, but rather, invasive vines and shrubs waiting to take over the landscape.

The woodlands are necessary for a functioning ecology. RPA’s in the Chesapeake Bay Preservation Act are vegetated areas along water bodies, such as lakes, streams, rivers, marshes or shoreline. RPAs are the last line of defense for the protection of water quality. These buffers stabilize shorelines and stream banks, filter pollutants, reduce the volume of stormwater runoff and provide critical habitat for aquatic species and wildlife. Trees and shrubs in riparian buffers reduce erosion, improve air quality, and provide shade in the summer, windbreaks in the winter and even store carbon.

About a decade ago the number of dead and dying trees had increased dramatically due to the emerald ash borer and it became obvious that the invasive vines, autumn olive and Japanese honeysuckle were choking out the natural renewal process. So, with guidance from the Forest Service and the Chesapeake Bay Act guidelines I began a project to restore my woodlands.   

First I called the  Virginia Department of Forestry to ask for advice. I did not know at the time that Prince William County had its very own forester. An Urban and Community Forestry Specialist from the Virginia Department of Forestry came out and inspected the woodland and made some recommendations.  He felt that with removal of the invasive vines and the hanging dead trees the wood might begin to renew itself. He put his recommendations in a report for me to submit to Clay Morris, Natural Resources Section Chief, Environmental Services Division of Prince William County Public Works to approve the work in the the RPA. Though the RPA covers just 2/3 of the woodland, I am treating all the wooded area in the same way. My proposal to Prince William County was strictly by the book in what is allowed in an RPA.   

It is slow work and expensive. Every winter a small crew hand cuts the invasive vines and then comes back in the spring to paint the cut stems of the invasive vines with herbicide. We are now in the fifth winter of my RPA and forest restoration process and are really beginning to see progress. I use "we" very loosely, Wetland Studies and Solutions is doing all of the actual labor, my husband and I are simply paying them and directing the sections to be done.  Here are a few pictures of the progress. 

This first picture is a section of the woodland before work began to remove invasive vines and plants in this area two years ago. It shows the trees covered in invasive vines. The vines were killing what life remained. We began by cutting the largest sections down with a chainsaw.


 2 years ago before work to remove invasives

In this second picture two years later it shows almost the same view after two years of work cutting out sections of invasive vines, extinguishing them with herbicide so they will not reattach to the base, removing some sections and letting vines dies and fall from the trees. Much of the cut wood was moved to make a pathway a section of which is seen above. 

This picture gives you a view of a section where the vines were cut and left to wither and die. Excessive amounts of cut vines and old barbed wire were removed. 

Wednesday, December 27, 2023

The Carbon Budget is almost used up


The following is from the press release from Imperial College London and the Study cited below:

Lamboll, R.D., Nicholls, Z.R.J., Smith, C.J. et al. Assessing the size and uncertainty of remaining carbon budgets. Nat. Clim. Chang. 13, 1360–1367 (2023).

Researchers at Imperial College London recently published a study in Nature Climate Change, that is the most up-to-date and comprehensive analysis of the global carbon budget. The carbon budget is an estimate of the amount of carbon dioxide emissions that can be emitted while keeping global warming below certain temperature limits.

In 2015 196 countries adopted  the Paris Climate Accord that was intended to put the nations on a course to reduce carbon dioxide emissions from the combustion of fossil fuels. The agreement was signed on Earth Day 2016 at the United Nations. The signing was a very hopeful moment. The Paris Agreement aims to limit global temperature increase to well below 2°C above preindustrial levels and pursue efforts to limit it to 1.5°C. The remaining carbon budget is one commonly used way to assess global progress against these targets.

The researchers state that previous found that global temperature rise is not strongly dependent on when carbon emissions occur, only on what the emissions cumulative sum is. However, the remaining carbon budget is strongly dependent on both how much and when different types of non-CO2 greenhouse gas emissions occur.  Using two models to account for this, the Imperial College London study estimates that for a 50% chance of limiting warming to 1.5°C, there are less than 250 gigatonnes of carbon dioxide left in the global carbon budget.

from the GCP

The researchers warn that if carbon dioxide emissions remain at 2022 levels of about 40 gigatonnes per year, the carbon budget will be exhausted by 2029, committing the world to warming of 1.5°C above preindustrial levels. To remain within 2°C above preindustrial temperatures humans need to emit less than 500 gigatons of additional carbon dioxide. At the current rate of emissions that is 12 years. There is still room for action in the 2°C above preindustrial level remaining carbon budget for global action.

Earlier studies had found that if carbon dioxide emissions continue at current levels, the remaining carbon budget to keep the global temperature within  2°C of preindustrial levels would be exhausted by 2046. The new study tells us that date is now 2036.

The finding means the budget is less than previously calculated and has approximately halved since 2020 due to the continued increase of global greenhouse gas emissions, caused primarily from the burning of fossil fuels as well as an improved estimate of the cooling effect of aerosols lost due to measures to improve air quality and reduce emissions.

The planet is faced with a huge challenge. Even if every nation met their current  pledge to reduce carbon dioxide emissions made in the Paris Climate Accord and its updates, the reductions promised are not enough to even maintain global temperatures within 2 °C above pre-industrial levels; and the nations are not meeting those pledges. Neither China nor India representing about a 40% of world carbon dioxide  emissions have committed to any reductions. Instead, they are projecting when their greenhouse gas emissions will peak and that is in more than a decade.

Sunday, December 24, 2023

Deicing Aircraft and their Pollution Contributing to Dead Zones

 The following has been excerpted from the USGS study and press release:

Airport Deicers: An Unrecognized Source of Phosphorus Loading in Receiving Waters
Owen M. Stefaniak, Steven R. Corsi, Troy D. Rutter, and Greg G. Failey
Environmental Science & Technology 2023 57 (44), 17051-17060
DOI: 10.1021/acs.est.3c03417

As winter approaches and temperatures get colder, removing ice and snow and preventing ice formation from aircraft and runways becomes essential for safe air travel. My husband and I met in Washington DC in the 1970’s and were a young married couple when just minutes after takeoff when in January 1982 Air Florida Flight 90 to Florida crashed into the 14th Street bridge killing 78 people. The cause was inadequate deicing and pilot error in responding to the problem. Had we not left DC for my husband's graduate work, we would have likely been on that bridge commuting into the District. 

Airports use a variety of products to remove or prevent ice and snow. Commonly used aircraft deicer and anti-icing fluids (ADAF) to remove ice, and anti-icers for inhibiting the formation of new ice on the aircrft. Use of these deicing products is required by the Federal Aviation Administration after a series of disasters in the last decades of the 20th century. during periods of ice and snow accumulation on aircraft.

These deicing agents usually contain chemicals that can affect local ecosystems. Stormwater runoff from airports is regulated and managed by airports. “Monitoring ice control product runoff is an important part of an airport’s pollution prevention plan, and in many cases, these plans include monitoring of phosphorus runoff,” says USGS Physical Scientist Owen Stefaniak, lead author of the study, “But accounting for the true source of phosphorus observed in airport runoff can be a real challenge for airport managers. Since these products contain proprietary ingredients not disclosed by the manufacturers, the airlines have no way to know how much phosphorus they are applying when they deice a plane.”

The new USGS study found that nine of eleven ice control product formulations used at airports contained phosphorus. Airports often take measures to reduce runoff from ice control products during freezing precipitation periods. In the coldest climates deicing pads drain to recovery tanks. However, preventing all runoff from aircraft and runway deicing operations during inclement weather while maintaining flight schedules is not typically possible.

Phosphorus exists naturally in the environment, but high levels can drive overgrowth of algae and plants, depleting oxygen and causing harmful algal blooms, fish mortality and habitat loss what is called a dead zone and is typically seen in summers. USGS scientists collected water samples during the deicing season as well as during the warmer months over a period of five years to see if airport ice control products were contributing to phosphorus pollution in local waterways.

The extent of each year’s dead zone is dependent on several factors, including how much nitrogen and phosphorus pollution enters waterways. High precipitation can contribute to the dead zone because it leads to more polluted runoff washing into rivers and streams from agriculture. In the Chesapeake Bay watershed we have had several warm winters in a row as well as lower than average dead zones. Precipitation was below average for most of 2023 delivering less nutrient pollution especially during the critical spring season, but it is unknown what impact if any the warm winters have had. 

The study was conducted in the area around Mitchell International Airport in Milwaukee, Wis., but the deicing products examined are extensively used at airports that experience freezing conditions nationally. During deicing periods, USGS found that 84% of the samples that were collected downstream of the airport had phosphorus that could likely be traced to ice control products, and 70% of the water samples had phosphorus levels that exceeded the Wisconsin Department of Natural Resources phosphorus aquatic life guidelines for streams, indicating potential for harm to the aquatic ecosystems receiving airport runoff.

The study focused on estimating how much phosphorus might be entering the streams from the ice control products, but it is still unclear how phosphorous from this source affects local ecosystems or whether this phosphorus is in a form readily available to aquatic organisms. Ice control product applications occur during freezing weather and phosphorus may not have the same environmental impact as it would during warmer months, when plant and algae growth is much greater.

Wednesday, December 20, 2023

Be Ready to Prevent Pipes from Freezing

Virginia has a moderate four-season climate that is typically humid in summers with mild winters, but there is tremendous variation over the Commonwealth and from year to year. There are those dry years, warm years, and cold and snowy years. Because of the usually mild winters here in Virginia, we do not often think of frozen pipes until an artic frost has arrived or when it is too late, and the pipes are already frozen. I was reminded this morning when I finally turned off the hoses. 

When sub-zero weather is in the forecast, we need to prepare our homes to prevent our pipes from freezing. According to Consumer Reports “burst pipes are one of the most common causes of property damage during frigid weather and can cost you thousands to repair. The pipes most at risk are those in unheated interior spaces such as basements, attics, and garages.” In Virginia, it is common to find bathrooms built above garages, or pipes running through the garage or an attic dormer. If you have a bathroom above a garage keep a small ceramic electric heater ($40) in the garage connected to a thermocouple that turns it on when the temperature in the garage falls below 40 degrees Fahrenheit. Turn on the heating cube in the garage and check it functioning when you turn off the hoses in late fall.

The likely pipes to freeze are against exterior walls of the home, or are exposed to the cold, like outdoor hose bibs, and water supply pipes in unheated interior areas like basements and crawl spaces, attics, garages, or kitchen cabinets. Pipes that run against exterior walls that have little or no insulation are also subject to freezing. It is easier to prevent pipes from freezing than to unfreeze them.

When the weather is forecast to fall into the single digits or lower open kitchen and bathroom cabinet doors to allow warmer air to circulate around plumbing, especially if your sinks are on an exterior wall or against attic dormers, and in the most extreme weather run an extra ceramic electric heater overnight keeping that bathroom toasty while the rest of the house is at an energy saving 65 degrees.

In sub-zero weather wells with and without separate well houses can freeze. Keeping the temperature in a well house above freezing or your well pipe insulated can prevent this. It used to be easy, that inefficient 100-watt incandescent bulb gave off enough heat to do the job, but now with more efficient bulbs, insulation and another source of heat is needed. An electric blanket can do the job. Deep wells are unlikely to freeze, it is usually a supply line not buried deep enough. Abnormally cold snaps can identify a private well line that was not buried deep enough at its most vulnerable point where it connects to the foundation.

Letting the water run in very freezing weather can work; however, can also create other problems. While running water may prevent the water supply lines from freezing, in the coldest weather the slowly running water might cause the drainpipe to the septic system (if you have one) to freeze and block the flow or even burst, and it can overwhelm a septic system. If you are on public water and sewer letting water trickle can prevent frozen pipes. You will see a significant increase in your water usage (still cheaper than repairing the damage from a burst pipe).

Frozen pipes can happen in your supply line or other parts of the house. There are things you can do to prevent frozen pipes. A couple of ceramic electric heat cubes, thermocouple, electric blanket, and a little strategy can prevent frozen pipes if there is heat in the home. However, electric heat pumps are extremely common in Virginia and becoming more so as various climate related programs push to transition to all electric households.

If the power should go out during a freeze, there may be no way to prevent the pipes in the home from freezing. Turning off the water at the main may be your best option if the power goes out and you do not have a generator or backup gas heat. Battery backups can help keep essentials running.

Whatever you do, do not run a gas-powered generator in the house and be wary of propane heaters not meant for interior use. We have a shop propane heater designed for indoor use and comes with an oxygen depletion sensor. These sensors detect the oxygen level in the air and turn off the propane. We also have battery operated carbon monoxide (CO) monitors throughout the house.

CO is an odorless, colorless gas that can kill you. This silent killer shows up any time you burn fuel, and it can quickly take over a home. Symptoms of carbon monoxide poisoning may resemble the flu (vomiting, dizziness, headache). So, use the CO monitors.

Sunday, December 17, 2023

Decentralized Water Treatment

To explore ways to lower costs and technology hurdles to distributed water treatment systems, National Alliance for Water Innovation (NAWI) and Stanford’s Water in the West convened a meeting of experts in February 2023 at Stanford University. Their  report was recently released and cited below summarizes the findings of the workshop that brought together researchers, industry experts, practitioners, policymakers and other stakeholders to discuss the current state of knowledge in extreme decentralized water treatment systems, and to identify the areas where further research and development are needed to allow the spread of this practice. All the comments of this blog entry are derived from the report of the workshop cited below.

Fairhart, A., Sedlak, D.L., Fiske, P., Kehoe, P., and Mauter, M. (2023). Extreme Decentralized Water Treatment. Exploring the Future of Premise-scale Water Treatment and Reuse: A Water in the West Series. Available at:

Access to an adequate quantity of treated and piped potable water and management of wastewater produced in homes and businesses is expected by all city dwellers and most suburban dwellers in wealthy countries like ours. Readily available safe drinking water and treatment of sewage is also crucial to public health and protection of the environment. For well over a century, municipal drinking water provision and wastewater management have been made possible by large investments in centralized systems. Fresh water withdrawn from rivers, reservoirs, and groundwater passes through drinking water treatment plants and is distributed through a vast underground pipe network to buildings throughout our urban and suburban communities.

After it is used, wastewater is collected in underground sewers that carry it to wastewater treatment plants to be cleaned to regulatory requirements prior to its discharge to the environment. In some water-stressed cities and locations like Northern Virginia some of the treated wastewater undergoes additional treatment to be directly or indirectly reused. This recycled water often is returned to users through another dedicated water distribution system recycling of the purple pipe water (non-potable by convention) in Loudoun County for data centers or in Fairfax for golf courses and ball fields. Alternatively, treated wastewater may be subjected to advanced treatment prior to being returned to the drinking water supply like delivering treated UOSA wastewater to the Occoquan Reservoir via release into the Occoquan River.

Although water reuse via the purple pipe system solves problems, the costs associated with the construction of a dedicated water distribution system for non-potable water throughout an entire area has high relative costs, regulatory complexities, and risks of unintentional cross-connections between recycled water and potable water pipes have limited the spread of such systems. The second approach, direct recycling is hindered in many places by the “ick” factor, but in locations like Northern Virginia, utilizing the Occoquan River to deliver the treated wastewater to the Occoquan Reservoir overcomes that. Another alternative, a relatively new approach to water recycling called decentralized water reuse may have promising advantages for utilities, developers, data centers and entrepreneurs.

Distributed water recycling systems have made considerable progress in cities where there is a recognition of the need to address water scarcity due to climate and growth and where partnerships have been built between utilities, building operators and regulatory authorities. The current generation of treatment technologies for distributed treatment typically recycle less than half of the wastewater produced within the building. In part, this is due to concerns about costs, but it is also determined by constraints put upon uses of recycled water in buildings. Although it is technically feasible to treat wastewater to a point at which it can be used for drinking, cooking and bathing, or to employ rooftop rainwater collection for potable purposes, such projects have rarely been built due to concerns about safety or the acceptability of the water.

With data centers, the bulk of the on-site water demand is for non-potable uses- cooling and watering of landscape. In a water-cooled system, water-cooled chillers and cooling towers located on top of the data center roofs produce chilled water, which is delivered to computer room air conditioners for cooling the entire building. In 2021, when Prince William County looked at water consumption for its 25 operational data centers at the time it found that water use varied by season and ranged from about 0.2 to 0.5 gallons per square foot per day. Prince William County Board of County Supervisors have recently approved rezonings that will ultimately result in tens of millions of square feet of data centers. Utilizing on-site water treatment could reduce the need for expansions of the UOSA plant, address part of the growing salinity problem, and reduce the cost of treatment for Fairfax Water.  

The workgroup at Stanford found that although existing technologies have proven to be adequate for the current generation of distributed water recycling systems, there is considerable room for improvement. NAWI was founded to conduct research research to lower costs and improve the feasibility of technologies that could help make non-traditional water sources a larger part of our nation’s water portfolio. In Japan more than 2,500 individual buildings in the country utilize in-building wastewater reclamation and rainwater harvesting systems, an alternative approach to centralized treatment that creates sustainable, resilient structures (Kimura et al. 2013). These systems treat different types of wastewaters within each building, including domestic sewage and graywater. The treated water is then used for various purposes like toilet flushing, cooling, garden watering, car cleaning and even fire protection. The emphasis in Japan  is on reusing water within the building where it was generated.

The shift towards building-scale water management has been facilitated by various factors, such as supportive local regulations, favorable tax policies, and technological expertise in designing and operating these systems. Further, the availability of a design manual and clearly defined water quality requirements for reclaimed water have further bolstered the adoption of on-site wastewater reclamation.

This approach has not worked as well in Bengalaru, India. The adoption of building-scale water treatment has not been as successful, the city’s journey features a blend of policy directives, innovative industry response and consumer-centric approaches (Miƶrner et al. 2023). Small-scale sewage treatment plants (SSTPs) are mandated to be included in all new construction and certain existing buildings. These systems are often contained within the building complex, treating wastewater for reuse in non-potable applications, like gardening and toilet flushing, contributing to a circular water economy at the community level.

Bengalaru, India lacks governance structures and regulatory standards, and the city grapples with ensuring accountability and quality in the rapidly growing ONWS market. Furthermore, concerns surrounding the health and safety of workers interacting with these systems underline the urgency for comprehensive regulation. Bengaluru’s story is one of policy-induced innovation and adaptation in the face of necessity. It serves as a reminder that while solutions can be replicated, execution of the solution will vary based on a variety of factors.

The factors for success identified in the report, would favor a distributed reuse for data centers. The bulk of water used on site is for non-potable purposes, the waste water tends to be fairly uniform in characteristics and there is a localized tremendous volume. The conversion of natural landscapes to impervious surfaces creates a stormwater problem whose solution could provide makeup water to the recycled on-site water. Virginia needs to work with NAWI and the data center industry to address this opportunity for sustainable water use.   Amazon Web Services (AWS) and Goggle have  commited “to be water positive by 2030.” Let’s see if we can do something to make all the data centers in Northern Virginia sustainable.  

Wednesday, December 13, 2023

COP 28 Ends

The 2023 United Nations Climate Change Conference or Conference of the Parties of the UNFCCC, more commonly known as COP28 ended yesterday. Government ministers representing nearly 200 countries on Wednesday agreed to a deal that calls for a transition away from fossil fuels, after a previous proposal was met with heated and widespread backlash. The agreement reached at COP28 failed to commit to a full fossil fuel phase out as hoped by many. While a commitment to end the use of fossil fuels was not achieved in Dubai, the outcome marks the beginning of the transition away from fossil fuels.

The final agreement published by the UAE earlier on Wednesday, was agreed on after all-night discussions, called for a “transitioning away from fossil fuels in energy systems, in a just, orderly and equitable manner, accelerating action in this critical decade, so as to achieve net zero by 2050 in keeping with the science.”

The deal text also urged for “accelerating efforts towards the phase-down of unabated coal power” and for “tripling renewable energy capacity globally and doubling the global average annual rate of energy efficiency improvements by 2030.”

Critically, the proposal did not mandate an absolute phase-out of hydrocarbons. However, COP28 did triple renewable energy targets, double energy efficiency goals, establishing a Global Goal on Adaptation framework, and beginning the operations of the loss and damage fund.  This is progress, the first pledges from wealthy nations were made in Dubai to support the fund.  The final text retains the calls for a doubling in adaptation finance and plans for assessments and monitoring of adaptation needs in the coming years. 

In his closing address at COP28, UN Climate Change Executive Secretary Simon Stiell  stressed the need for faster progress to keep the 1.5-degree pathway viable. “Whilst we didn’t turn the page on the fossil fuel era in Dubai, this outcome is the beginning of the end,” said Mr. Stiell, who simultaneously acknowledged, “We’re currently headed for just under 3 degrees.  This still equates to mass human suffering, which is why COP28 needed to move the needle further. The global stocktake showed us clearly that progress is not fast enough, but undeniably it is gathering pace.” He further acknowledged the crucial role of ordinary people in driving climate action, and concluded by stating that UN Climate Change remains committed to supporting every step of the journey in the race to a sustainable future.

Sunday, December 10, 2023

Global Carbon Budget 2023

 The COP 28 meeting continues, but the news release last week from the Global Carbon Project is not good. Their report shows what a big lift it will be to meet the promises of the Paris Accord. 

The Global Carbon Project is an international research project and partner of the World Climate Research Programme. The Global Carbon Project aims to develop a complete picture (quite literally with incredible infographics) and integrates all the knowledge of greenhouse gases, human activities and the Earth system. They were founded in 2001 to fully understand the carbon cycle on our planet. Their projects include global budgets for the three dominant greenhouse gases (carbon dioxide, methane, and nitrous oxide) and track growth in and source of emissions, performance against the Paris Accord commitments and efforts in urban, regional, cumulative, and negative emissions. The just released  Global Carbon Budget 2023 is the source of the below comments.

The people at the Global Carbon Project found that CO2 emissions from fossil use are projected to rise 1.1% in 2023, reaching 36.8 billion tonnes of carbon dioxide (GtCO2).  Growth took place in all fuel types (coal, oil, natural gas). This brings fossil CO2 emissions to a record high 1.4% above the 2019 pre[1]COVID-19 levels.

While emissions are declining in 26 countries, these efforts remain insufficient to reverse the growth in global fossil fuel emissions in China and India. Growth in total CO2 emissions for our planet – the sum of fossil and land-use change emissions are projected to be 40.9 GtCO2 in 2023. While growth in total CO2 emissions has slowed down over the past decade, emissions continue to grow leading to a continued increase in CO2 in the atmosphere and continued global warming.

from GCP

The atmospheric CO2 level is projected to average 419.3 ppm in 2023. This is 51% above pre-industrial levels. If current CO2 emissions levels persist, the remaining carbon budget for a 50% chance to limit warming to 1.5°C could be exceeded in 7 years - essentially eliminating any pathway to holding global temperatures within 1.5°C of preindustrial levels. Though many countries have reduced their fossil CO2 emissions or slowed the growth in emissions, progress is not fast enough and not widespread enough to put global emissions on a downward trajectory towards net zero. 

from GCP

The preliminary data for 2023 show global fossil CO2 emissions are set to reach a record high, with an increase of about  +1.1% (range 0.0% to 2.1%) relative to 2022 level, and expected growth in all fuel types. Projected 2023 emissions decrease in the European Union, USA, and to a lesser extent in the Rest of the World were exceeded by increases in emissions in India and China. Fossil fuel CO2 emissions in India are now above those of the European Union.

from Green Risks

In China (31% of global emissions), emissions in 2023 are projected to increase by 4% (range 1.9% to +6.1%) over 2022. A strong rise is projected for emissions from coal (+3.3%), oil (+9.9%) and natural gas (+6.5%). Growth in 2023 is partly caused by a delayed rebound from significant COVID-19 lockdowns in China in 2022.

In the United States (14% of global emissions), emissions in 2023 are projected to decrease by 3.0% (range -5.0% to -1.0%) over 2022. Decreases are projected for emissions from coal (-18.3%) and oil (-0.3%), while there is a projected rise in emissions from natural gas (+1.4%). The sharp decline in coal emissions is largely driven by a continuation of retirements of coal-fired power stations and cheaper natural gas since 2022. The rise in natural gas consumption in the power sector is largely offset by reduced heating demand resulting from milder winter temperatures in 2023.

In India (8% of global emissions), emissions in 2023 are projected to increase by 8.2% (range 6.7% to 9.7%) over 2022, with projected rises in emissions from coal (+9.5%), oil (+5.3%), natural gas (+5.6%), and cement (+8.8%). Coal growth is largely driven by high growth in demand for power, with new renewables capacity far from sufficient to meet this growth. Emissions in India are now above those of the European Union. India is building coal power generation. Just converting coal generation to natural gas would almost halve emissions. 

In the European Union (EU27, 7% of global emissions), emissions in 2023 are projected to decrease by 7.4% (range -9.9% to -4.9%) over 2022, with projected decreases in emissions from coal (-18.8%), oil (-1.5%), and natural gas (-6.6%). Consumption of both coal and natural gas have been driven down by increased renewables capacity and the continued effects of the energy crisis, with high energy prices and other inflationary factors leading to lower energy demand.

from GCP

International aviation and shipping (2.8% of global emissions) are projected to increase by 11.9% in 2023. It is believed by some that emissions from data centers has already exceeded that level and is growing at a very rapid rate.

Wednesday, December 6, 2023

2023 Dead Zone December Update


At the end of November the Maryland Department of Natural Resources, Old Dominion University, and Virginia Institute of Marine Science announced that the dead zone in the Chesapeake Bay this year was the smallest since monitoring began in 1985. 

The “Dead Zone” of the Chesapeake Bay refers to a volume of hypoxic water that is characterized by dissolved oxygen concentrations less than 2 mg/L, which is too low for aquatic organisms such as fish and blue crabs to thrive. Within the hypoxic area life of the bay dies and a “Dead Zone” forms. The Chesapeake Bay experiences hypoxic conditions every year, with the severity varying from year to year, depending on nutrient and freshwater flows into the bay, wind, and temperature and season. Dead zones form in the warmer months.

The extent of each year’s dead zone is dependent on several factors, including how much nitrogen and phosphorus pollution enters waterways. High precipitation can contribute to the dead zone because it leads to more polluted runoff washing into rivers and streams. Precipitation was below average for most of 2023 delivering less pollution especially during the critical spring season.  

The spring-time nutrient supply to the Bay was relatively low and June was relatively windy, both of which may have contributed to June through August having a low amount of hypoxia. The Dead Zone remained at low to moderate levels throughout June, July, and into August. The Potomac basin has experienced unusual dryness, despite sporadic heavy rains.  Low stream flows carried less nutrients into the rivers. The cumulative deficit over the past 12 water year was around  6 inches in the basin as a whole.

from VIMS

Each year the Maryland Department of Natural Resources measures the actual dissolved oxygen at several points during the summer months in the Maryland portion of the Chesapeake Bay main stem and the size of the Dead Zone. While the Virginia Institute of Marine Science (VIMS), Anchor QEA and collaborators at UMCES, operate a real-time three-dimensional hypoxia forecast model using measured inputs that predicts daily dissolved oxygen concentrations throughout the Bay ( using the National Weather Service wind monitoring data.

Sunday, December 3, 2023

EPA Proposes updated rules for Lead Water Pipes

Last week the U.S. Environmental Protection Agency (EPA) announced a proposal to strengthen its Lead and Copper Rule that would require water systems across the country to replace all lead service lines within 10 years. EPA is also proposing lowering the lead action level down to 10 ppb and improving sampling protocols utilized by water systems. 

EPA estimates that there are 9.2 million lead service lines.  This proposal is expected to cost between $45 billion and $60 billion. There is no funding associated with this proposed change in the Lead and Copper Rule (though the Bi-Partisan Infrastructure bill has $15 billion for lead removal). Water utilities and citizens will have to figure out how to pay for this mandate. Typically, these service lines are owned by both the water utility and the property owner. It is common that utilities only own the portion of the service line until it reaches the property line. However, there are many places like Fairfax where the service line is entirely owned by the property owner it serves. When Washington DC replaced many of their service lines they only replaced the portion that the utility owned leaving the portion of the lead service line owned by the property in place. This often resulted in increased lead exposure from the disturbed line. The proposed rule requires replacement of the entire lead service line.

This is an important regulation because lead can cause damage to the brain and kidneys, and can interfere with the production of red blood cells that carry oxygen to all parts of your body. The greatest risk of lead exposure is to infants, young children, and pregnant women. Scientists have linked the effects of lead on the brain with lowered IQ in children. I am amongst the many scientist who believe there is no safe level of lead exposure. If your home was built before 1990 the only way to know if you have lead in your drinking water is to test.

The U. S. EPA limit for lead in drinking water is currently 15 parts per billion (ppb), but only requires action if limited sample monitoring for lead has exceeded the 15 ppb action level in more than 10% of the homes tested. Cities are only required to test a very small number of homes monthly and the condition and age of the plumbing in the home really determines if lead levels will be elevated.

Lead in drinking water is a national problem mostly associated with older urban areas.  Lead in drinking water predominately coms from the pipes. Lead does not exist in most groundwater, rivers and lakes- the source water for most municipal and private water supplies. Instead, lead in drinking water is picked up from the pipes on its journey into a home.

In the early years of public water supply the water service lines delivering water from the water main in the street into each home were commonly made of lead. This practice began to fade by the 1950’s but was legal until 1988. Lead was also used to solder copper pipes together before 1988 (when the 1986 ban on lead in paint and solder went into effect). Also, until very recently (2011 Reduction of Lead in Drinking Water Act) almost all drinking water fixtures were made from brass containing up to 8% lead, even if they were sold as "lead-free." So even homes built with PVC piping in the 2000’s may have some lead in most of the faucets.

Elevated lead levels can also be a problem for well owners. Lead leaches into the water primarily as a result of corrosion of plumbing and well components. Brass fittings and adaptors usually contains lead levels of 8% or less, but this can still dissolve lead into the water, especially during the first few months of use or in a corrosive water environment. Older submersible pumps had brass components which are a source of lead. Corrosion control techniques such as adjusting pH or alkalinity that are commonly used in public systems are not common in private wells where the decision to install and maintain treatment is solely the prerogative and responsibility of the homeowner. As a result, though 26% of the private wells tested in the  Virginia Rural Household Water Quality program had pH outside the neutral range of 6.5-8.5 , only 5% of private well systems had acid neutralizers installed to control pH and corrosion within the home and 3% had reverse osmosis units that could remove lead among other contaminants. Lead in drinking water is picked up from the pipes and plumbing fixtures on its journey into a home.

The strengthening of the Lead and Copper rule will address many of these risks and  appears to be an improvement that will better protect our inner city communities that are most impacted by lead in drinking water. All lead service lines should be replaced. Those of us on public water need to push to have all lead service lines in our communities replaced. Addressing sources or lead in the home (old copper pipes with lead solder, faucets predating 2014 and the problem of lead in down well equipment will remain the problem of the homeowner.