About 5500 bce or around 7,600 years ago, just north of what is now Turkey was a valley with a large plain with a very large freshwater lake in the center. The geniuses who estimate population say that there were between 1 and 15 million humans living at the dawn of agriculture, about 10,000 years ago. Since this lake valley was probably very habitable and welcoming â and right in the middle of the arc of civilization â thousands of people must have lived and practiced their primitive farming along the shore.
Just a couple thousand years before this time, an Ice Age had ended. Glaciers that had covered most of Northern Europe were melting and receding. This was good news for the Lake People. Glacier water is fresh water, and their lake got its water from several rivers that came from the north. These rivers were fed by glaciers that were melting in what are now Russia and Ukraine.
Unfortunately for the Lake People the blessing of the fresh glacier water brought with it a terrible curse.
The melting of the glaciers across Northern Europe meant another thing: the sea levels of the worldâs oceans were rising. As the level of the Atlantic Ocean rose, so too did the level of the Mediterranean Sea. As the level of the Mediterranean Sea rose, the water climbed up to what was then a valley between Greece and Turkey. First it inundated what is now the Dardanelles Strait. Then, as the water climbed a little further to the northeast, it inundated a basin creating what we today call the Sea of Marmara. Relentlessly the water kept climbing to the northeast until it reached the crest. On the other side was our large, flat valley with its enormous lake and thousands of farmers.
Finally, the rising water of the Mediterranean Sea began to spill over the crest. Very slowly it dribbled at first. But as it continued to dribble, it began to wash away the soil on the crest. This made the crest lower, allowing more and more Mediterranean Sea water to spill into the valley.
At a critical moment, the flow accelerated exponentially. The more water that came over the crest, the more the crest was washed away, and the more and the faster the water flowed. Once the flood reached a critical level, the crest caved in and the water became a massive torrent.
At its peak, scientists estimate that the flow over the crest had the force of â20 Niagarasâ. Niagara is the largest waterfall in North America. Water flows over Niagara Falls at a rate of 6 million cubic feet per minute. So 20 Niagaras would have meant 120 million cubic feet per minute. There are about 7.5 gallons of water in a cubic foot. So, that means that at the peak of the flood about 900 million gallons per minute of seawater were pouring into the valley.
The Lake People must not have noticed much at first when the flow was small. And it was probably small for several years. But when the crest broke and the flood reached its peak, the scientists say that the water in the lake rose at a rate of 1 foot per hour. At this rate, there was no escape. There was no way any of the people in the valley could get out. They all â all â perished. Every one of them â every man, woman, and child â drowned.
The villages along the lake are now buried under water about 6,600 feet of the Black Sea.
When the waters of the Mediterranean Sea were only a few feet deep along the crest, shepherds used to cross their cattle there. The term âcattle crossingâ in Greek is called bous-poros. Today we call this place the Bosporus Strait. The shepherds canât cross their cattle there any more: the straits that the cattle used to walk across are now over 200 feet deep.
The Lake People didnât know it but the process that melted the glaciers is called âglobal warmingâ. They were some of the first people to learn about âclimate changeâ.
For several decades now, we have been hearing the drumbeat about how Earthâs climate is changing â how it is getting warmer. That is certainly true. We have been experiencing the end of the last Ice Age for the last 11,000 years. The same process that killed the Lake People. So we too are experiencing global warming.
But this time, itâs not just Sun and Earth that are involved in the process. No, now itâs us humans too. Since the beginning of the Industrial Revolution about 300 years ago, we have been adding to the global warming process. We have been aggravating it.
We have been making Earth warmer by adding industrial gases into the atmosphere that trap Sunâs heat. Because this process resembles the atmosphere inside green houses, the industrial gases that we add to Earthâs atmosphere are collectively referred to as âgreenhouse gasesâ and the resultant warming is called the âgreenhouse effectâ.
Scientists tell us that we humans add 30 billion tons of CO2 per year to the atmosphere!
The Lake People knew firsthand about global warming. But they knew nothing about it other than the fact that the water in their lake was rising. They had no clue that there were glaciers in Russia and Ukraine, much less that they were melting, much less that this was affecting something called an ocean that was thousands of miles away. The Lake People didnât know it, but they were living in what scientists call an âinterglacialâ. This is the name given to the periods when glaciers are retreating and melting. The opposite â times when Earth is cooling and the glaciers are growing â is called âglacialsâ.
Over the last 2 billion years, there have been five Ice Ages. Scientists can tell by examining core samples taken from both land and from the massive polar ice caps that have been in place since Earth was formed 4.5 billion years ago. They have had to bore down thousands of feet to find the evidence from the fossils and sediments that were on the surface of Earth eons ago. The interglacial that killed our Lake People began only about 11,000 years ago. It is still going on today. Five million years earlier, where the Mediterranean Sea now sits, there was then an enormous valley, which was a vast desert. At the end of another Ice Age back then, the level of the Atlantic Ocean broke through the land bridge at Gibraltar and filled the entire basin east of there with seawater. That bit of global warming actually created the Mediterranean Sea. This was the exact same process that took place when the level of the Mediterranean Sea rose, broke through the Bosporus land bridge, and flooded the valley where our Lake People lived that we now call the Black Sea.
It was a long time between the tragedy of our Lake People and the time when we humans first caught on to the periodic heating and cooling of our planet. The science of Ice Ages and global climate is relatively new. Only in the last four centuries have scientists began to study Earth and its climate and, more importantly, Sun and its effect on Earthâs climate.
It wasnât actually until the 19th century that scientists began to think that Earthâs atmosphere underwent periods of hot and cold over very long periods of time. In fact, it wasnât until the 1920s that a Serbian scientist, Milutin Milankovitch, realized that variations in Earthâs orbit were causing variations in the amount of solar radiation reaching Earth. The three orbital variations are: (1) changes in Earthâs orbit around Sun (eccentricity), (2) shifts in the tilt of Earthâs axis (obliquity), and (3) the wobbling motion of Earthâs axis (precession). In other words, it was Earthâs tilt and wobble that was causing the hot and cold spells. In the scientific community, these became known as Milankovitch Cycles. In simpler and more popular terms, they became known by their most pronounced effects: Ice Ages.
James Edward Hansen is a distinguished physicist who directs the Program on Climate Science, Awareness, and Solutions at the Earth Institute at Columbia University. On June 23, 1988, Dr. Hansen was invited to testify before the Committee on Energy and Natural Resources of the United States Senate. During his testimony he didnât exactly coin the terms âglobal warmingâ or âclimate changeâ; but he might as well have. Because it was then that these two complementary concepts began to creep into the consciousness of modern Americans.
President George H. W. Bush promised to work for climate change mitigation. Both he and his appointed administrator of Environmental Protection Agency (EPA), Bill Reilly, did work that led up to the United States participating in the Rio Summit in 1992, which Bill Reilly attended. However, from then on, progress at the federal level slowed down. During the 2000s, the action shifted to the states. Notable in these developments were governors Pataki in New York, Schwarzenegger in California, and Romney in Massachusetts. California adopted both Clean Car Standards as well as a comprehensive climate program. When Barack Obama became the president in 2008, he organized several major initiatives.
Rather than attempting to deal with a cranky Congress, the Obama Administration started using the authority that already existed in the Clean Air Act to promulgate regulations on vehicles and electric utilities.
Upon taking office in 2017, President Donald Trump made good on his pledge to withdraw from the Paris Accords. But as soon as he did so, Governor Andrew Cuomo in New York and Governor Jerry Brown in California formed the United States Climate Alliance declaring their intent to honor the Accord. Seventeen states are now members of this Alliance. Since then, both Hawaii and Connecticut have adopted the legislation to make significant reductions in greenhouse gas emissions.
Both California and New York also made important commitments to energy storage capacity. New York pledged 1,500 MW of storage by 2025 and California pledged 1,300 MW. In addition, California has created financial incentives for the sales of âZero Emission Vehiclesâ (ZEVs). Nine more states have followed suit, including Connecticut, Maine, Maryland, Massachusetts, New Jersey, New York, Oregon, Rhode Island, and Vermont.
So, in the United States we have a history of strong action to reduce global warming by many states. As of this writing, it is expected that the Biden Administration will reverse Donald Trumpâs anti-climate actions and will certainly rejoin the Paris Accords and will resurrect many of the pro-climate change policies of the Obama Administration.
The United Nations Conference on the Environment and Development was held in Rio de Janeiro in 1992. The meeting was called the âEarth Summitâ.
But the genesis of this concern, as well as a more generalized concern for the environment itself, occurred in the late 1960s, both in the United States and around the world.
In 1969, the United Nations General Assembly decided to convene a conference to formulate policy alternatives for governments facing environmental issues. And so, the United Nations Conference on the Human Environment happened in Stockholm in 1972, the same year that the U.S. Congress passed the Clean Water Act.
Eleven years later â now even more haunted by the impact of industrialization on the environment â the U.N. Secretary General created the World Commission on Environment and Development (WCED), which soon took on the name of the Commissionâs dynamic chair, the former Norwegian prime minister, Gro Harlem Brundtland, and became known as the âBrundtland Commission.â
In October of 1987, the Brundtland Commission issued its report entitled âOur Common Future.â In this document, they defined â for the first time â the term âsustainable development.â They defined sustainable development as âdevelopment that meets the needs of the present without compromising the ability of future generations to meet their own needs.â
In addition, âOur Common Futureâ set the stage for the âEarth Summitâ in Rio in 1992, where the common concept of climate change was born.
Two of the major issues that were taken up in Rio were: (1) alternative sources of energy to replace fossil fuels linked to global warming and climate change, and,(2) a new reliance on public transportation to reduce vehicle emissions. The Rio conference, which lasted 6 months, produced two major declarations: (1) âAgenda 21â, which was a blueprint/action agenda for achieving sustainable development, and (2) the âRio Declaration on Environment and Development,â consisting of 27 principles to guide sustainable development.
But, by far, the most important outcome of the Earth Summit was the negotiation of the United Nations Framework Convention on Climate Change (UNFCCC). The purpose of this groundbreaking treaty was âto stabilize greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous human interference with the climate system.â As of today, there are 194 nations that are signatories to this agreement. The United States originally signed the agreement but then withdrew in 2017.
One of the provisions of the UNFCCC is that the parties would convene each year to assess progress. These meetings are called Conferences of Parties (COPs). In 1997, the COP was held in Kyoto, Japan, where a further agreement was reached known as the infamous âKyoto Protocolâ.
The Kyoto Protocol set binding limits for developed countries on the emission levels of six greenhouse gases: carbon dioxide, methane, nitrous oxide, sulfur hexafluoride, hydrofluorocarbons (HFCs), and perfluorocarbons (PFCs). The emission limits were set at 1,990 levels. In other words, each developed country was to reduce the emissions of these six gases to 1,990 levels.
The Kyoto Protocol was ratified by all members of the United Nations except Afghanistan, Andorra, Canada, South Sudan, and, most notably, the United States.
In addition, the Kyoto Protocol also established a system of assigning allowances of emissions, especially CO2, and permitted the trading of these allowances or credits. This resulted in what the British call the âEuropean Trading Schemeâ, and the rest of us Anglophones, who are leery of the word âschemeâ, call the âEuropean Trading Systemâ (ETS).
As part of this trading system, the Kyoto Protocol also created what is called the âClean Development Mechanism (CDM)â. This is a program where, for example, a developing country that wants to build a fossil-fueled power plant ...