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General

What About the Floridian Aquifer in Georgia?

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After my last post on whether the Floridian Aquifer in Florida was in water bankruptcy (according to the definition from the United Nations University Report entitled Global Water Bankruptcy) I was contacted by a reader of this blog from Georgia. He gets his water from a small municipal system supplied by wells into the Floridian aquifer. I explained in my first post on the Floridian: An Aquifer is All About Its’ Geology that the Floridian aquifer extends into southern Georgia, South Carolina and Alabama. The situation in Georgia where my reader lives is quite a bit different from Florida. Let’s take a look and see if the Floridian in Georgia could be classified as being in water bankruptcy.

As usual when discussing an aquifer we’ll start with the geology. The Georgia and South Carolina parts of the Floridan aquifer are at the northern most edge of the broad carbonate platform that underlies much of Florida and the adjacent Coastal Plain. The Eocene and Oligocene limestone and dolostone formations of the Floridian dip and thicken towards the coast with more purely limestone and dolostones of Eocene and Oligocene age. The main formations are the Ocala limestone and the Suwannee Limestone which were deposited in shallow marine environments as lime muds, skeletal debris and reef and shoal deposits.  After burial and consolidation, the carbonates were altered by recrystallization and through carbonate dissolving along fractures – similar to the Floridian’s formations in Florida. Up dip, toward the Fall Line where coastal sediments meet the metamorphic and igneous rocks of the Piedmont the carbonate formations become thinner, more discontinuous, and increasingly mixed with siliciclastic sediments.

The aquifer is overlain by younger rock formations comprised of clay, silt, sand, phosphates, and unconsolidated surface deposits of Miocene, Pliocene, Pleistocene, and Holocene age that serve to confine the aquifer and restrict surface recharge. The formations of the Floridian in Georgia are recharged where they outcrop at the surface near the Fall Line.  This is very different from Florida where formations of the Floridian outcrop over much of the surface of the state and water recharge to the aquifer is direct. Because of this indirect recharge, water that enters the Floridian aquifer near the Fall Line takes thousands of years to reach the coast. I hope people who use the water along the coastal plain think about that when they leave the tap running.

Just as in Florida, the aquifer is divided into the Upper and Lower Floridian. Intervening between the carbonate formations comprising the Upper and Lower aquifer are marls and siliclastic rocks; however, they are not continuous throughout Georgia and sometimes the Upper and Lower Floridian are connected. And just like Florida, the Upper Floridian is the more prolific of the two with much better water quality, although still “hard”, containing high levels of calcium and magnesium.

The Upper Floridian has been a traditional source of water in Georgia for municipal, agricultural and industrial needs. Unfortunately, that all had to change. The reason: saltwater intrusion. I discussed saltwater intrusion in my blog on the Floridian aquifer in Florida. You can read it here ( IS THE FLORIDAN AQUIFER  SUFFERING WATER BANKRUPTCY?  ). In short, the formations of an aquifer do not stop at lands end. No, they continue on beneath the ocean. In Georgia it is fortunate that the formations of the Floridian are overlain in most places by fairly thick overlying rocks, so saltwater from the ocean does not intrude into the aquifer. Not so in South Carolina. Hilton Head is the offending area. The local absence and erosion of these overlying rock formations have resulted in saltwater intrusion.

As you can see from the figure above taken from the Georgia Environmental Protection Division website, the area called the Beaufort Arch is where the problem exits. In the past when sea level in the Hilton Head area, including the Calibogue Sound west of the island, was lower ancient rivers cut right through the overlying rocks and formed channels. Later these channels filled with younger porous sediments. These channels can act as conduits for seawater to move downward into the Upper Floridian aquifer.

This might not sound like all that much of a problem, but because the Floridian aquifer was so overused on the southern coastal plain in Georgia it resulted in water in the aquifer moving from South Carolina towards the centers of pumping in Georgia. All sorts of towns and municipalities in Georgia, including Savannah and Brunswick, used the Upper Floridian aquifer as their main source of water. Before this large-scale groundwater development, freshwater in the Upper Floridan aquifer moved generally from inland recharge areas in South Carolina toward the coast and discharged upward or seaward. Under those natural conditions, artesian pressure helped keep saline water offshore or beneath the freshwater system. Hilton Head had increased vulnerability because the island lies close to Port Royal Sound, Calibogue Sound, and other saline surface-water bodies that overlie or border parts of the Floridan aquifer system there. It’s not all Georgia’s fault though, after all Hilton Head Island also was withdrawing water from the Upper Floridian which lowered the water table and reversed the aquifer’s natural seaward hydraulic movement. United States Geological Survey studies of Hilton Head have clearly shown how declining aquifer pressure changed the groundwater flow direction beneath the island. Instead of freshwater consistently moving toward Port Royal Sound, portions of the aquifer began moving landward.

To add insult to injury for the Floridian aquifer in Georgia, over pumping in the Brunswick area has caused another type of saltwater intrusion. The Upper and Lower Floridian aquifers are more integrated in that area because of faulting and fracturing in the rock formations. The Lower Floridian is not of high quality. Due to over pumping this low-quality saline water was drawn upward into the Upper Floridian aquifer. The problem is most significant in downtown Brunswick.

During the 1980s efforts began in Georgia to prevent saline waters from destroying the Floridian aquifer. Georgia began limiting water withdrawals from the aquifer in the most vulnerable coastal areas, especially around Savannah. The major turning point came in 1997, when the Georgia Environmental Protection Division adopted the Interim Strategy for Managing Salt-water Intrusion in the Upper Floridan Aquifer of Southeast Georgia. The strategy covered twenty-four coastal counties and imposed caps or reductions in areas where additional pumping could worsen saltwater movement. It required areas around Savannah to reduce groundwater use by at least 10 million gallons per day by the end of 2005 and limited new withdrawals in other parts of the coastal area.

Georgia replaced the interim strategy with the Coastal Georgia Water and Wastewater Permitting Plan for Managing Saltwater Intrusion in 2006. The plan instituted a more detailed management system for the Floridian aquifer. In the Savannah area where saltwater encroachment from the Hilton Head side was a central concern, the plan continued to limit Upper Floridan withdrawals and encouraged the shift to alternative sources, including surface water. Savannah now gets its’ water from the Savannah River. Smaller communities with no access to surface water have very restrictive limits on withdrawal and major water conservation measures are in place.  In Brunswick where the saltwater plume was already wreaking havoc on water-quality, the plan preserved withdrawal restrictions. Brunswick has responded with conservation measures and drilling wells into less productive aquifers to supplement their water supply. And Hilton Head? Well, they have chosen to drill a very deep well into Eocene rocks. It’s poor water quality but they have added a desalination plant using reverse osmosis to treat it.

Is the Floridian in Georgia in water bankruptcy. I say no. Good management practices early on have disrupted such a catastrophe. This hydrograph from the USGS shows the rebound of water levels in Coastal Georgia after the institution of Georgia’s aquifer control measures.

 But the Floridian around Hilton Head in South Carolina might well meet the definition of water bankruptcy as once salinization occurs you’ve wrecked your water supply permanently.

General

Ocean Acidification 2021

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This is my fourth and final post on the 2021 report: Climate Change: The Physical Science Basis by the United Nations International Panel on Climate Change. I promised four posts covering ocean warming, sea level rise, salinity changes, and finally the subject of this post – ocean acidification. Acidification sounds scary doesn’t it? You might imagine a big rolling sea of water that can burn your skin off. It’s not that bad, but it’s still somewhat frightening. Now I don’t mean to scare people through my blog, that’s big media’s business. I want to inform people who don’t have the time to read thousands of pages of scientific documents about their contents. My blog posts are designed to provide you with a nuts and bolts synopsis of critical water issues plaguing the world today. But sometimes the data can be pretty worrisome.

So let’s get the scary bit out of the way shall we. The IPCC report points to the oceans absorption of carbon dioxide since the 1980s as being in the range of 20 to 30 percent of all human carbon emissions. As a consequence the pH of the ocean surface has declined 0.017 to 0.027 units per decade since the 1980s and subsurface pH up to a mile in depth have declined by 0.003 to 0.026. If you want to know more about how carbon dioxide impacts ocean pH you can find it here https://waterblogger.org/general-information/ocean-acidification-climate-change/ .

You may be asking yourself why such a small decline in pH is so scary. We have to do some chemistry to explain. As the ocean water absorbs carbon dioxide from the air a chemical exchange occurs, producing carbonic acid – H2CO3. The carbonic acid dissociates, generating HCO3 and H+. What this means is that carbonate ions (CO3) in the water are decreased and bicarbonate (HCO3) ions are increased. It basically changes the whole carbonate chemistry of the ocean. You might not care but all the little critters that make their shells from calcium and carbonate in the ocean’s water do.  Calcium carbonate saturation rates of seawater have been declining at rates of 0.07 to 0.12 per decade.

What I find particularly fascinating in the 2021 IPCC report though is the variation in pH decrease that has been measured in different parts of the ocean now, for example the tropical Pacific Ocean is decreasing in pH at a greater momentum than other ocean areas, while the western tropical Pacific Ocean (renowned for its warm pool of water) shows slower pH declines. Coastal areas are acidifying at a greater rate than elsewhere as waters there are supersaturated with carbon dioxide. What’s happening at depth is interesting too. The well known meridional overturning circulation zones, such as the one in the Atlantic Ocean characterized by the Gulf Stream, bring warm water from the lower latitudes into the Polar Regions where it cools and sinks thereby producing acidification in the deep ocean. Areas like the subpolar North Atlantic Ocean and the Southern Ocean have the highest acidification found at depths greater 2 miles.

Governments are busy trying to decrease carbon dioxide emissions. The results will reverse ocean acidification at the surface, but not at depth due to the long time scales of ocean turnover. This will result in a lasting legacy in the deep ocean and impact biological resources for thousands of years to come.

General

Ocean Salinty and Climate Change

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Ocean salinity is not a topic people often think about when it comes to climate change. After all why in the world would the salinity of the oceans change just because human produced greenhouse gases like carbon dioxide are accumulating in the atmosphere and the ocean? There’s a simple answer to this question though and I explained it in a detailed blog post about six years ago. You can read it at your leisure ( https://waterblogger.org/general-information/ocean-salinity-climate-change/  ). The short answer for the sake of brevity in this post is that greenhouse gases are causing the atmosphere to warm and warm air holds more moisture resulting in increased rainfall. If the amount of rain exceeds the amount of evaporation then a body of water becomes fresher and if there’s more evaporation than rain the water becomes more saline.

 This is all measurable and scientists have been measuring atmospheric water vapor since the 1970’s. It is raining more over the Pacific Ocean where there is already a lot of warmth with accompanying atmospheric moisture and it is raining less in the mid latitudes of the Atlantic Ocean. The Pacific Ocean is becoming less salty and the Atlantic Ocean saltier. Scientists in fact have been measuring the very dickens out of the oceans saline content. There are measurements through the Soil Moisture and Ocean Salinity (SMOS) satellite system and ARGO’s 2000 plus ocean based floating instruments. The latest 2021 International Panel on Climate Change report entitled Climate Change: The Physical Science Basis indicates that between 1950 and 2019 trends in near surface ocean waters have shown strengthening of the contrast between high and low salinity areas of the ocean. The report quantifies the increase in contrast as 0.14 parts per thousand. This is up slightly from the 0.13 parts per thousand reported in the 2013 IPCC report of the same name.

So what if some parts of the ocean are getting saltier and others are getting fresher? Who cares? Well scientists are concerned that changes in salinity will affect the density of ocean water as higher saline content results in denser water while fresher water is less dense. Ocean density is already being impacted by temperature changes. Cold water is denser than warm water. Certain deep water circulation patterns in the oceans are dependent on dense surface water sinking in the polar regions, for example the Atlantic Meridional Overturning Circulation (AMOC). AMOC brings warm surface water from the equatorial region of the Atlantic Ocean to the northern Atlantic where it cools, sinks and is transported back towards the equator. It’s like a big conveyor belt in the ocean. Scientists say that AMOC impacts the climate of the Northern Hemisphere but they seem quite uncertain as to how. They suspect it keeps conditions a lot warmer in the Northern Hemisphere than it would otherwise be. But all they really know is what is measurable and what is measurable is that AMOC is weakening. This makes sense if polar waters are warming and denser saline waters in the middle latitudes of the Atlantic are not being transported to the poles breaking the chain of the Atlantic Ocean circulation. If you live on the east coast of the United States you are probably familiar with AMOC as it includes the Gulf Stream which moves warm water from the Gulf of Mexico along the coast of the United States and Canada then on up to the Northern Scandinavian countries. Scientists are also uncertain as to what exactly is going to be the result of a weakening AMOC. There is of course a lot of speculation by researchers often based on what occurred in the geologic past when AMOC weakened. The IPCC report though does not take a position on the veracity of the various studies purporting to know exactly what happened when AMOC weakened in the past nor are they even a hundred percent sure if the weakening of AMOC is being caused by climate change. The IPCC report says that the record is too short to determine if weakening of AMOC is natural variability or driven by climate change. So I won’t speculate either, I’ll leave that to the popular press.

General

Sea Level Rise from Climate Change

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High water marks on a bulkhead

I read a story in the newspaper a few weeks ago about how the governor of Florida was visiting Miami in order to start the long process of providing protection from sea level rise to the low lying city. It was an interesting article; because in addressing the issues caused by sea level rise, like coastal inundation and flooding, he wouldn’t let the words climate change pass his lips even though the issues have expensive solutions like sea walls and drainage infrastructure. I’m not a political person but it seems strange to me that the guy won’t address the root cause of the problem and is only interested in temporary fixes. Sea level rise is becoming an acute problem all up and down the eastern seaboard of the U.S. wherever development has occurred along the coast. I live on an island where gauges to measure sea level have been installed to track the inevitable encroachment of the ocean. I’m afraid our community won’t exist in 50 years as no manner of temporary fixes will keep the island from disappearing.

Six years ago I wrote a blog post on the rising oceans (https://waterblogger.org/general-information/sea-level-rise-climate-change/ ). At the time scientists used satellite measurements to show there was a 0.03 inch yearly rise of sea level as the result of greenhouse gas emissions. Increased monitoring since then has produced a lot of new and better data, so let’s take a look at what the just released 2021 report from the United Nations International Panel on Climate Change Climate Change 2021: The Physical Science Basis has to say about sea level changes.

Here are the yearly sea level rises given in the 2021 report:

PeriodAverage Rate of Sea Level Rise in Inches per Year
1901 – 19710.05
1971 – 20060.075
2006 – 20180.15
Data from 2021 UN IPCC Climate Change 2021

What can we make of this new data? Simple math indicates that over the last 12 years of monitoring sea level has risen 1.8 inches and the total sea level rise from 1901 to 2018 is estimated at close to 7.9 inches. My last blog post based on the 2013 IPCC report on the physical science basis for climate change had an estimate of a 7.5 inch rise over the time period between 1901 and 2013. So we’re not talking about a huge increase in 8 years, but you can see from the table above that a continuous sea level rise is going on and that the rate of the rise is increasing on a yearly basis.

Why is sea level rising so quickly? Sure glaciers are melting and the Greenland Ice Sheet looks like swiss cheese because it has so many holes in it, but according to the 2021 IPCC report glacial melt has only caused about 41 % of the sea level rise between 1901 and 2018, although it is projected to increase as the loss of ice sheets is really beginning to take off and now accounts for 35 % of the sea level rise that has occurred between 2006 and 2018. The other reason for the sea level rising is simply good old fashioned thermal expansion. When you heat water, it expands. The 2021 IPCC report estimates thermal expansion is causing 38 % of sea level rise.

Other factors playing into higher sea levels are density and circulation changes in the ocean; however the 2021 IPCC report fails to quantify their contribution. I find it hard to believe because there are a multitude of other facts and figures given, but really the report just doesn’t say. There’s often a failure to communicate in the IPCC report caused chiefly by omissions like this one but also because so many different time periods and measurements are compared. It’s a hard slog to get through the whole report and garner any useful information. My literary critique aside, the changes caused by thermal expansion (thermosteric changes) and density changes from increased salinity (halosteric changes) are lumped together in the 2021 IPCC report as “steric sea level change.” These two changes actually should be working at cross purposes to each other, as greater density decreases volume whereas higher temperatures increase volume. I would take exception to how they are presented in the report, except in reality the halosteric changes are negligible.

So this is probably more complex than you ever thought and then to put even more of a spin on things (excuse the pun) sea level rise is not the same everywhere due to the earth’s rotation and gravity. In other words your sea level rise in Thailand is not going to be the same as it is in say New York City because water is sloshing around and mounding up differentially.

What is causing the sea level to rise is probably not as important as the projections in the 2021 IPCC report for future changes in sea level. The 2021 IPCC report provides two different calculations for future sea level rise: one projection is for the scenario of greenhouse gases being substantially reduced and the other is for a scenario where they continue to be emitted at high levels. Compared to the time period between 1995 and 2014 calculations show that in 2150 global mean sea level will rise by about 2 feet for the low emissions scenario and by 55 feet in the high emissions scenario. Unfortunately the world is now beyond the tipping point of totally eliminating sea level rise because heat in the surface of the ocean is slowly circulating into the deeper parts of the ocean and will be retained there, causing thermal expansion for thousands of years to come.

General

Ocean warming -climate change

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I wrote my first blog post on ocean warming in 2016 (https://waterblogger.org/general-information/increase-in-ocean-temperatures-climate-change/). Almost six years have passed so let’s take a look at the state of the science in determining how our planet’s oceans are responding to the additional heat being transferred to them from the atmosphere. Conveniently the latest report from the International Panel on Climate Change (IPCC) just came out in 2021. It is entitled Climate Change 2021: The Physical Science Basis and is written in a much different style than the last IPCC report of the same name issued in 2013, because the science of climate change has grown. There’s a lot more certainty among scientists about what green house gas emissions from human activities are doing to our planet because there has been substantial data collection from a global network of monitoring systems over the last decade. Even the climate models have been updated and the predictions are now more useful. The bulk of the 2021 IPCC report is geared toward risk. In other words what is going to happen to this planet if it continues to warm and more importantly to readers of this blog, what is going to happen to the oceans?

The report uses a period between 1850 and 1900 as a reference period for comparison to today’s temperatures. You may recall those years were the beginning of industrialization. Scientists can now say definitively that global surface temperatures in 2021 are 2.1 degrees Fahrenheit higher than the time between 1850 and 1900.    

I wrote about ARGO in my very first post on how warming is affecting the oceans (https://waterblogger.org/general-information/oceans-and-climate-change/  ). ARGO is a system of floating scientific instrumentation deployed in the oceans around the world. The instruments measure, among other things, ocean temperature. The array of monitors has helped scientists determine the ongoing increases in ocean heat content in at least the upper 6500 feet of the ocean where measurements are being taken. Below 6500 feet there’s just not much data. But in the upper 6500 feet things are really warming up because these are the ocean depths where the ocean is storing heat from the atmosphere. Back in 2013 studies estimated that 90 % of earth’s energy caused by global warming since the 1970s is being stored in the ocean. New calculations say 91 %. Not much change there, but ARGO has been able to further refine for climate scientists where among the various depths of the ocean heat storage is concentrated. As you can imagine the first 3000 feet of the ocean is taking the big brunt of the action with 61 % of the total. This is important to realize because mixing and transfer of heat among the ocean layers is very slow. Later on in this blog post I’ll tell you why this is so important, but first a few more facts and figures for you from the report.

As everyone knows by now the three main greenhouse gases that are drivers of climate change are carbon dioxide, methane, and nitrous oxide. Carbon dioxide, which is in large part responsible for warming temperatures, is being exchanged and buffered by the ocean. Buffering is when carbon dioxide interchanges chemically with the water at the ocean’s surface to form a new compound – a weak carbonic acid. The ocean is taking up not only most of the heat from the atmosphere but is at the same time storing and reducing the amount of carbon dioxide. Carbon dioxide increases have been measured to be about 1.56 ppm a year over the last 61 years. During this time the accumulation of carbon dioxide in the atmosphere has remained about the same – 44 %. Why? Because the carbon is being taken up by the oceans and by the plants and soils of the planet. The circulation within the ocean slowly moves the carbon from the surface into deeper parts of the ocean.   

Scientists measure carbon in PgC. One PgC is equal to a billion metric tons of carbon. That’s a lot. The calculation of the cumulative amount of carbon dioxide from human activities that has been stored in the ocean is about 105 PgC. Do the math. Total human emissions of carbon dioxide are estimated to be 450 PgC. So the ocean is taking up 23 %. The fascinating thing that has been calculated in the 2021 IPCC report is when exactly the ocean will lose its buffering capacity for carbon dioxide. This is a mere chemical calculation, nothing special. Here’s the result: the ocean should be able to uptake carbon dioxide from the atmosphere through 2100, but its capacity to buffer will start decreasing around 2050.

What does this mean? It means that more carbon dioxide will remain in the atmosphere. For decades half of carbon dioxide has been taken up by the ocean and terrestrial carbon sinks and has slowed warming of the atmosphere. In 2050 the atmospheric temperatures will start to rise. You think its hot now, just wait.

And for the oceans? Average ocean temperatures today have increased by 1.6 degrees Fahrenheit from the reference period of 1850 to 1900. Since the 1970s, heat transfer to the oceans has increased by 0.28 – 0.55 yotta joules. No that’s not lotta joules; it’s yotta joules. Although it seems like a lot of joules to me. This a very large number, greater even than my calculator can handle. Take 0.28 and add 24 zeroes behind it. The 2021 IPCC report estimates that in the future ocean heat is likely to increase by 2 to 4 times that amount and 83 % of the ocean surface will warm over the 21st century. And here is what I told you earlier that I’d reveal later in this post. Even if green house gas emissions are drastically cut back, ocean warming will continue until 2300 because of the slow circulation between the upper and lower ocean depths.

So there you have it, the dystopian future of the oceans is sealed.

General

First Contact: Climate Change

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I can envision the future when aliens first arrive in 2150 to contact humanity. Gyzzzzlbex and Azzterixx stop at the United Nations building in New York City for a meet and greet.

            Gyzzzzlbex looks around and says, “Hey Azzterixx I don’t remember all this water covering up the city. I know it’s been two hundred years since we last visited this planet, but I’m sure there wasn’t this much water here then.”

            Azzterixx replies, “And where are all the people? I didn’t see a soul when we were on the way down here in our space ship. This planet was heavily populated when we last visited.”

            “Maybe they killed themselves off with those nuclear bombs they were testing in the desert when we had that hard landing in Roswell, New Mexico.”

            “Nah,” says Azzterixx, “My monitor doesn’t show any radiation.”

            “Well maybe there’s something here in the United Nations headquarters that will tell us what happened.”

            The two aliens look around in the various rooms and find a library.

            Azzterixx picks up a weighty tome, browses through it, then says, “Well look here Gyzzzzlbex, this document says that it is unequivocal that humans have warmed the atmosphere, ocean and land of this planet through release of green house gases and that there have been widespread and rapid changes to the atmosphere, oceans, cryosphere and biosphere as a result.”

            Gyzzzzlbex walks over to where Azzterixx is standing and tries to read over his shoulder. “What is that big book you are quoting from?”

            Azzterixx says, “It’s called Climate Change 2021: The Physical Science Basis. It’s by some panel of experts here at the United Nations called the International Panel on Climate Change. And holy cow it is 4000 pages long.”

            Gyzzzzlbex says, “How about turning the page there Azzterixx.”

            Azzterixx does so and they both inhale sharply.

            “So that’s what killed them all,” says Gyzzzzlbex.

            “Yes and they calculated it all out in this report. Amazing. They knew if they didn’t drastically cut green house gas emissions that the global surface atmospheric temperature could rise by as much as 12 degrees Fahrenheit by 2100. How sad. Well I guess our mission here is done.”

            As the aliens turn to leave Gyzzzzlbex says, “I wonder why they did nothing to stop green house gas emissions, knowing what they did?”

            I wonder too. I read the news coverage of the recent United Nations Climate Summit in Scotland which reported of a consensus among scientists and environmental organizations that the agreement reached there by some 200 countries will not be enough to mitigate greenhouse gases impacts on our climate. It’s been since January 2016 that I’ve written anything on how climate change is impacting the oceans, so I thought I’d take a hard look at the scientific research presented by the IPCC report on Climate Change: The Physical Science Basis just issued in 2021 versus the report by the same name from 2014. I wrote four posts on climate change in 2016 that covered:  ocean temperature changes, sea level rise, and ocean salinity. So I’m going to follow that process again in this blog to let long time readers catch up with the current science. Here is a link to the first post I wrote in 2016 (https://waterblogger.org/general-information/oceans-and-climate-change/ ).

General

Repeal of the Clean Water Rule

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The Administrator of the U.S. Environmental Protection Agency (EPA) and the Assistant Secretary of Civil Works for the U.S. Army (essentially the Corps of Engineers since they implement portions of the Clean Water Act) signed a “Recodification of a Pre-existing Rule” on September 12, 2019.  According to the summary in the text, the Recodification “repeals” the Clean Water Rule of 2015.  I have written multiple times in this blog on the complicated regulatory and legal issues surrounding the Clean Water Rule of 2015.   For background check out these links: https://waterblogger.org/water-quantity/waters-of-the-united-states/

          The item being recodified is the definition of the “Waters of the United States” (WOTUS) under the Clean Water Act (CWA), or in simpler terms, what bodies of water are regulated under the Clean Water Act.  In a nutshell the Clean Water Rule of 2015 was seen by many states as a water grab by the federal government, because states have traditionally managed waters within their boundaries and the new definition expanded the water bodies covered by the CWA.

          However the definition of WOTUS which existed prior to the Clean Water Rule of 2015 was difficult to implement and a number of regulatory decisions made by federal agencies to include wetlands and water bodies adjacent to tributaries as WOTUS were appealed by landowners through the court system.  A couple of these cases reached the Supreme Court.  The Supreme Court directed the federal agencies to provide a resolution as to what bodies of water were WOTUS.  As a result the EPA rewrote the regulations and used a science based approach to do so.  The new regulations published in 2015 were dubbed The Clean Water Rule. 

          These rewritten regulations were a spectacular failure and since 2015 there has been an ocean of litigation.  Lawsuits were brought against the Clean Water Rule by a group of 28 states.  This litigation resulted in judgments that stopped implementation of the Rule in those states.  Those 28 states have been operating under the original regulations ever since.  The other 22 states have been operating under the new 2015 Clean Water regulations. 

          The purpose of the Recodification is to reinstate the original regulations which existed before the 2015 Clean Water Rule was implemented.  With the Recodification all 50 states will be operating under the original regulations – at least until whatever new litigation gets underway.  The Recodification text gives four reasons that support the repeal.

          First, a Supreme Court decision dictated that the EPA and the Corps of Engineers needed to define the limits of their authority to implement the CWA.   The 2015 Clean Water Rule failed to do so.  (A lot of states envisioned that the lack of a limitation could lead to every drop of water in the U.S. being subject to the CWA.)

          Second, the 2015 Clean Water Rule didn’t recognize, preserve, and protect the primary responsibility and rights of the states to manage their own land and resources.  (The western states and the big agricultural states jealously guard their right to manage water within their state boundaries so the Clean Water Rule, by expanding the federal government’s regulatory authority over water bodies, really riled them up.)

          Third, without any authorization from Congress the 2015 Clean Water Rule provided a regulatory framework that could have led to encroachment on the state’s land use planning authority.   (States were concerned about traditional state and local authority over land use activities like conversion of land for agricultural and other uses.)

          Lastly, the 2015 Clean Water Rule’s attempt to define the scope of a tributary or adjacent waters inclusion under the CWA resulted in some procedural errors and lacked adequate record support.  (Basically a couple of court cases said EPA didn’t meet the arbitrary and capricious standard under the Administrative Procedures Act.  It looked like the agency while writing the final regulations had just pulled a bunch of numbers out of a hat to define the distance a tributary or adjacent water had to be from a WOTUS to be included as a regulated water body.)

          The Recodification has not yet been published in the Federal Register so it is not yet being implemented.  It is also being called “Step 1.”  After the Recodification, “Step 2” will be implemented.  “Step 2” just happens to be a new Rule defining WOTUS.  This new rule published for comment in 2018 tries to simplify the definition of a “WOTUS” by making it a legal definition instead of a definition based on science.  A description of this new Rule can be found at this link: https://waterblogger.org/general-information/revised-rule-on-the-definition-of-waters-of-the-united-states/

          Stay tuned.  I’ll keep you up to date as the regulation winds its way through further trials and tribulations. 

General

Revised Rule on the Definition of “Waters of the United States”

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On December 11, 2018 the Acting U.S. Environmental Protection Agency (EPA) Administrator Andrew Wheeler held a live video announcement about the upcoming release of the revised regulatory rule on the definition of the “Waters of the United States” – also referred to by some as the Clean Water Rule. According to Wheeler, the rule will be advertised in the Federal Register within the next four weeks but will also be posted in advance on the EPA website. Once the Rule is advertised in the Federal Register, there will be a 60 day public comment period. Wheeler stated during the question and answer session of the video announcement: “the rule will allow you to stand on your own property and tell whether it is a water body under Federal jurisdiction.”  

General

Ocean Acidification – Climate Change

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When I took my first graduate level physical chemistry class many years ago, I had a professor who spent several lectures demonstrating how the human emission of carbon dioxide through the burning of fossil fuel could not contribute to the accumulation of greenhouse gases in the atmosphere and cause atmospheric temperatures to rise. His chemical equations showed how ocean water reacts with carbon dioxide in the atmosphere and essentially removes it.  The chemical equations for this exchange are actually very simple and quite well known. Carbon dioxide, which is CO2 (carbon and oxygen), reacts with water, which we know is H2O (hydrogen and oxygen), to form carbonic acid (H2CO3). Carbonic acid then further reacts with ocean water to produce bicarbonate (HCO3) and free hydrogen ions.

You’re thinking, we’re saved! We don’t have to worry about those carbon dioxide emissions from power plants and cars anymore. Let’s pump more oil and gas out of the ground and to heck with driving a Prius. Where’s my Hummer?

Well not so fast. My physical chemistry professor forgot to explain to us what happens to the ocean after this chemical exchange. What do we remember about free hydrogen ions? They are a measure of acidity. Remember pH? It is a scale of measurement from 1 to 14 where 7 is neutral. Anything below 7 is acidic and anything above 7 is basic. The pH of a solution is simply a measure of free hydrogen ions. The more free hydrogen you have, the more acidic your solution. So when the ocean reacts with carbon dioxide from the atmosphere, it is becoming more acidic. This is what is known as ocean acidification.

The pH of the oceans range from 7.8 to 8.4. So right now seawater is mildly on the basic side. The pH of the oceans is something scientists have been measuring for a long time. The change in the pH of the ocean can also be calculated based on man’s carbon dioxide emissions. Scientists have made an inventory of greenhouse gas emissions dating as far back as the start of the industrial age. Such inventories are not your most accurate of measures, especially when you are looking at emissions from several hundred years ago, but if anything they are probably undercounting emissions. The International Panel on Climate Change in their 2013 Report “The Physical Science Basis” states that currently the amount of total carbon dioxide from human emissions being stored in the ocean is 30 %. According to calculations using such inventories there has been a 0.08 decrease in pH in the ocean’s surface water between 1765 and 1994.

Direct measurement of pH taken since 1991 in the North Atlantic and North Pacific have shown a steady decrease ranging between ‾0.0014 and ‾0.0024 per year. These numbers reflect regional variations in pH decreases. The IPCC report states the variability in the decline of pH is a reflection of high latitude oceans not as effectively absorbing carbon dioxide.

The pH decreases seem tiny don’t they? But think about this. Oceans cover almost three-fourths of our planet; that is a lot of water. The fact that carbon dioxide emissions can change the pH of the entire surface water of the ocean every year by even these tiny amounts is phenomenal. Say you took the mid-range of this yearly decrease (‾0.0019) and multiply it by 1000 years. You would be looking at almost a pH decrease of 2 by the year 3016. You would be going from slightly basic ocean water to slightly acidic ocean water, just from human carbon dioxide emissions.

On the short term there are a lot of scientific researchers who are studying the impacts that these slight yearly decreases may be causing. None other than the National Academy of Sciences has weighed into the impacts of ocean acidification by developing  “A National Strategy to Meet the Challenges of a Changing Ocean (2010).” Ocean Acidification is a big concern of scientists, after all humans are changing the very chemistry of the earth’s oceans.

General

Ocean Salinity – Climate Change

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Have you ever read the folktale “Why the Sea is Salt?” It’s a cute little story about a magic handmill spirited away from Satan himself by an unfortunate thief. While hiding behind the door to hell, the thief sees the devil order the handmill to produce all sorts of lavish food and objects. Once he gets his hands on the magic handmill, the thief escapes by boarding a boat and setting sail. The devil had directed the handmill by simply saying “handmill grind…,” so the thief proceeds to tell the magic handmill to grind gold. Unfortunately for the thief, only Satan can make the handmill grind luxuries. For everyone else, the magic handmill just grinds salt. Once the handmill starts grinding salt, the thief realizes he’s forgotten the words the devil used to get the handmill to stop. The salt from the handmill overloads the boat and it sinks to the bottom of the ocean where the handmill keeps on grinding out loads of salt even today.

It’s a nice legend, but in reality we all know the main mechanism causing the sea to be salty is the erosion of minerals from rocks and soils. The eroded minerals are flushed down rivers and streams and deposited in the oceans. There’s also some contribution of minerals to the oceans from volcanic eruptions both above and below sea level. (Yes there are volcanic eruptions from the ocean floor.) The minerals in the ocean are concentrated by evaporation of freshwater from the ocean’s surface. Some of these minerals like calcium and carbonate are used by organisms to form shells. Other minerals are used as nutrients. Only the minerals which are not actively used by organic life in vast amounts are left behind. As you might guess the largest component of the dissolved solids left in the oceans are chloride and sodium, the components of salt. Useful for seasoning French fries but not much else.

With all you’ve heard in the media about the melting glaciers and the polar ice sheets, you would think the ocean was getting less salty, right? After all, the freshwater from all this ice is going into the ocean and scientists say that at least half of sea level rise is being caused by melting ice. Surely this addition of freshwater is having an impact.  In reality though the contribution of melting glaciers to salinity changes in the oceans is not as great as you might think, because there are a whole lot of other things going on between the oceans and the atmosphere which are far more influential on how salty the water is. The International Panel on Climate Change (IPCC) in their 2013 report “The Physical Science Basis” states that the oceans are getting saltier in some locations and less salty in others. For example the Atlantic Ocean is becoming saltier and the Pacific Ocean is becoming fresher.  Interestingly enough, the Atlantic has always been saltier than the Pacific. Why? It is that old hydrologic cycle of evaporation and precipitation. It just rains more in the Pacific.  Low salinity is found in areas where precipitation exceeds evaporation and runoff from rivers and streams. High salinity is found where evaporation exceeds precipitation and runoff.

Increases in atmospheric temperature as part of climate change increases this overall hydrologic cycle. Think about it. Warmer air holds more moisture than dry air. The IPCC cites that the atmosphere can actually hold about 4 % more water vapor for each degree Fahrenheit the temperature increases. Scientists have been recording atmospheric vapor since the 1970s and the data show increases in atmospheric water vapor. So essentially, it is raining more in warm areas of the Pacific Ocean and raining less in mid latitude areas of the Atlantic Ocean. The IPCC report notes that surface salinity of the tropical Pacific Ocean has declined by 0.1 – 0.3 parts per thousand over 50 years in the western equatorial regions and by up to 0.6 – 0.75 in the intertropical and southern Pacific. The subtropical Atlantic is saltier by 0.1 – 0.3. Polar regions also get more precipitation in the form of both ice and snow, so the ocean water in the arctic regions is becoming fresher as well, although I didn’t see an exact number in the IPCC report.

Interesting right? But exactly how vital is the role of salinity in the oceans? Colder water is denser than warmer water. Denser water sinks. In the arctic, cold fresh water sinks and spreads toward the equator, supplying the deeper ocean with freshwater and reducing salinity. It is a process that impacts the oceans circulation and ocean circulation impacts our climate. Fresh water is less dense than salty water. Will the freshening of the waters in the arctic impact the movement of polar waters in some way? Will increasingly dense salty water in the subtropics result in changes to the composition of deeper water? Now we are entering the realm of speculation. Other scientists don’t hesitate to speculate on possibilities. No less an august organization as the National Science Foundation speculates that based on research they funded back in the early first decade of the 21st century  fresher water at the northern pole could impact ocean circulation in the North Atlantic, in particular the Gulf Stream, and consequently weather in the Northern Hemisphere.

The impact of the Gulf Stream on North Atlantic climate appears to be as much of a myth as the thief’s magic handmill, according to the Lamont Doherty Earth Observatory at Columbia University. Here is a link to an article on why the Observatory says it is a myth:

http://www.ldeo.columbia.edu/res/div/ocp/gs/.

So I will leave speculation about the impacts of changes in ocean salinity to earth’s climate for someone else.