Climate Science is Not New

As someone who both writes and gives talks on climate change, I often meet people with doubts about the subject who ask: “Climate science is so new, how can we trust it?” The answer is simple. It is not new. In fact, the fundamentals of climate science have been understood for close to 200 years.

One of the first scientists to look into the planet’s energy balance was Joseph Fourier, a French physicist, in the 1820s. Given the Earth’s distance from the Sun, he was curious to know why its temperature was not cooler. Fourier felt that something other than incoming solar radiation was keeping the planet warm and hypothesized that the atmosphere was somehow acting like an insulating blanket. Working with the limited technology of the day, however, he was unable to make the detailed measurements needed to carry his idea further.

Decades later, in the 1860s, an Irish scientist named John Tyndall picked up Fourier’s theory. An alpine adventurer, he was interested in glaciers and the then controversial idea of ice ages. Wanting to know more about how they formed, he devised an experiment to see if the Earth’s atmosphere was acting like a thermostat. For this, he built a spectrophotometer – an instrument that measures the amount of heat that gases can absorb. His experiments showed that water vapor, carbon dioxide (CO2), and methane were all very efficient at trapping heat. This essentially proved Fourier’s idea of a greenhouse effect.

In the 1890s, Svante Arrhenius, a Swedish physicist, followed up on Tyndall’s idea of an atmospheric thermostat and ran with it. Ruling out water vapor as too transitory, he focused on carbon dioxide, which tends to linger in the atmosphere for a long time. His calculations showed that doubling the amount of carbon dioxide in the atmosphere would raise the average global temperature by 5°C (9°F).

To understand if such a large-scale change in atmospheric CO2 was possible, he turned to Arvid Hogbom, a colleague studying the global carbon cycle. This is the natural geochemical process where volcanic eruptions and the chemical weathering of rocks release CO2, while plants and oceans absorb it. Hogbom confirmed that CO2 levels could change dramatically over long periods of time. However, he also noted that industrial processes were releasing a significant amount of CO2 relatively quickly. Using this information, Arrhenius calculated that human activities, such as burning fossil fuels, could alter the composition of the atmosphere and increase global temperatures. In the 1890’s, however, fossil fuel use was only a fraction of what it is today and he believed it would take more than 1,000 years for the level of atmospheric CO2 to double.

Jumping ahead to the 1950s, Charles David Keeling, a researcher at the Scripps Institution of Oceanography in California, found a way to directly monitor levels of CO2 in the atmosphere. He created an instrument called a gas chromatograph and installed it on top of Mauna Loa in Hawaii. At an elevation of more than 11,000 feet in the middle of the Pacific Ocean, it is removed from both direct CO2 sources like factories and sinks such as forests that could skew the data. Still in operation today, the information recorded at this station is known as the Keeling Curve. It shows the steady increase in CO2 levels in the atmosphere from 1958 to present.

Keeling’s measurements provided solid evidence that CO2 levels were rising and validated the theories of Tyndall and Arrhenius. More recently, scientists were able to extend his curve back in time by analyzing ancient air bubbles trapped in ice-cores from Greenland and Antarctica. This lengthy record shows that pre-industrial CO2 levels in the atmosphere were about 280 ppm. Today, they are over 400ppm – the highest they have been in more than 800,000 years.

Seeing this dramatic rise in CO2 and realizing the impact that a warming climate could have on society, the UN formed the Intergovernmental Panel on Climate Change (IPCC) in 1988. They assess the peer-reviewed research of thousands of scientists from around the world and publish a synthesized view of the current science. The latest IPCC report (AR5 published in sections in 2013/2014) unconditionally states that human activities are the main drivers of modern climate change.

Therefore, while it is the nature of all science to evolve with time and research, it is safe to say that climate science is not a new subject. It is only relatively new to those in the political sphere.

Giants in the history of climate science.

Outcomes of the UN Climate Change Conference in Marrakesh

The UN Climate Change Conference in Marrakesh, known as COP 22, concluded on Saturday. Building on the momentum of the 2015 Paris Agreement, it began the process of putting the details of that historic accord into action.

Years in the making, the Paris Agreement set the target of holding global warming to 2°C (3.6°F) above pre-industrial levels. To achieve this goal, nearly 200 countries submitted individual voluntary emissions reduction plans known as nationally determined contributions (NDCs). Based on the current collection of NDCs, which vary widely in ambition, the agreement will only cut greenhouse gas emissions by about half of what is necessary to reach the 2°C (3.6°F) goal. It does, however, legally obligate countries to publically report how much emissions they have actually eliminated and to reassess their plans every five years.

One of the main goals of the Marrakesh meeting was to create a standardized rulebook to monitor and report on these independent undertakings. But after two weeks of negotiations and to the dismay of those hoping for quicker action, the diplomats agreed on 2018 as the deadline for setting up this vital framework. The finance of climate adaptation – the touchy subject of who will pay for what in terms of helping poor nations adapt to climate change – was also punted two years down the road. However, they did issue the Marrakech Action Proclamation re-affirming their commitment to the Paris Agreement and their promises to combat climate change.

Although ratified in record time, the Paris Agreement is a fragile accord. All commitments are voluntary and vulnerable to the political will of individual governments – both now and in the future. Moreover, there are no penalties for those who do not live up to their promises. This is why the election of Mr. Trump as the next US President sent shockwaves through the meeting in Morocco.

The President-elect has famously called climate change a “hoax” and said he would withdraw the US from the Paris Agreement. While only time will tell if Mr. Trump will follow through on his rhetoric of climate change denial, the rest of the world seems willing to move forward with plans to tackle this critical issue.

Outside of the formal COP meetings, the positive spirit of the Paris Agreement pushed forward. Four countries – Canada, Germany, Mexico and the US – announced their climate action plans through 2050. With one of the more aggressive proposals, Germany aims to essentially stop using fossil fuels and reduce its emissions between 80% and 95% by mid-century. Furthermore, a group of forty-eight developing nations, members of the Climate Vulnerable Forum, declared their intention to switch to 100% renewable energy between 2030 and 2050.

The Marrakech meeting was the 22nd session of the Conference of the Parties (COP) to the U.N. Framework Convention on Climate Change (UNFCCC). The next conference (COP 23) will take place in November 2017 in Bonn, Germany.

Credit: UN

Credit: UN

The UN Climate Change Conference in Marrakesh is Underway

COP 22, the UN Climate Change Conference in Marrakesh, Morocco, is underway. The goal of this massive meeting is to turn the ideas outlined in the 2015 Paris Agreement into action.

Years in the making, the Paris Agreement set the target of holding global warming to 2°C (3.6°F) above pre-industrial levels. To achieve this goal, nearly 200 countries submitted individual voluntary emissions reduction plans known as nationally determined contributions (NDCs).

Moving into the next phase of this historic agreement, the diplomats attending the Marrakesh meeting will hash out the framework needed to monitor and report on these independent undertakings. The ideal system would involve an independent panel with consistent standards that monitors countries to see if they are following through on their greenhouse gas reduction pledges. This type of reporting, it is believed, would encourage accountability as it applies the power of public scrutiny. Some countries, however, are expected to argue for a self-monitoring system. China and India, two of the world’s largest polluters, are likely to push for this less public path.

Another big topic at the Marrakesh meeting will be money. During the Paris talks last year, the wealthy nations of the world said they would create a fund and spend $100 billion a year to help poor nations adapt to climate change. Negotiators will have to work out the details of where and how this money be spent.

Although ratified in record time, the Paris Agreement is still a fragile accord. All commitments are voluntary and vulnerable to the political will of each individual government. Moreover, there are no penalties for those who do not live up to their promises.

That said, expectations going into Marrakesh are high as governments around the world have shown a willingness to act on climate change outside the parameters of the Paris Agreement. Last month, global leaders agreed to reduce the use of hydrofluorocarbons (HFCs), a potent greenhouse gas commonly used as a coolant in refrigerators and air-conditioners. They also agreed to make airplanes more fuel-efficient and reduce the overall carbon footprint of air travel.

The Marrakesh conference runs through November 18.

Credit: UN

Credit: UN

Paris Climate Change Agreement Enters into Force

The Paris Climate Agreement is signed, sealed, and delivered. Approved domestically by the requisite number of signatories with unusual speed, it will enter into force in 30 days.

The historic deal negotiated at the UN Climate Change Conference in Paris last December required ratification by 55 countries, representing 55% of global greenhouse gas emissions before it could go into effect. This double threshold was passed this week when the EU, Canada, and a number of smaller states officially ratified the agreement. To date, according to the UN, 72 countries representing more than 56% of emissions have signed on to the deal including the US, China, and India – the world’s three largest carbon polluters.

The aim of this international agreement is to limit global warming to 2°C (3.6°F) above pre-industrial levels. To achieve this goal, it employs a mix of voluntary and legally binding actions. While every country submitted their own emissions reduction plan known as nationally determined contributions (NDCs), there was no requirement quantifying the amount of greenhouse gases they had to cut or how it had to be done. Additionally, there are no penalties for those who do not live up to their promises. Instead, the accord depends heavily on global peer pressure and the hope that no country wants to be seen as a slacker in the eyes of the world.

Based on the current collection of national plans, which vary widely in ambition, this agreement will only cut greenhouse gas emissions by about half of what is necessary to reach the 2°C (3.6°F) goal. The accord, however, does legally obligate countries to publically report how much emissions they have actually eliminated and to reassess their plans every five years.

While flawed, the Paris Accord is the world’s first truly global climate agreement. It marks the culmination of a very long, and often tumultuous, international political process that began at the Rio Earth Summit 24 years ago. That said, the hard part still lies ahead.

Individual nations need to stay the course and implement the commitments in their NDCs. The framework needed to monitor and report on these independent undertakings will be negotiated at the next UN Climate Change Conference (COP22) in Marrakesh, Morocco this November. The Paris Agreement will come into force on November 4th.

Paris Climate Change Agreement has met the double threshold required to enter into force. Credit: UN

The Paris Climate Change Agreement met the double threshold required to enter into force on October 5, 2016. Credit: UN

The Paris Climate Change Agreement is Signed at UN on Earth Day

On this Earth Day, government officials from around the globe are gathered at the UN headquarters in New York City to sign the historic climate change deal that was hammered out in Paris last December. This signing ceremony is one of several steps needed to put the global accord into effect.

Known as the Paris Agreement, the deal aims to limit global warming to 2°C (3.6°F) above pre-industrial levels. To achieve this goal, countries submitted individual five-year plans called “intended nationally determined contributions” or INDCs. They essentially spell out how much CO2 a country plans to cut based on its own political and economic situation. Under the current collection of national plans, however, the Paris Agreement will only cut greenhouse gas emissions by about half of what is necessary to reach the 2°C (3.6°F) goal. That said, the agreement does legally obligate countries to reconvene every five years to present updated plans detailing how they will deepen their emissions cuts.

The next step in the UN process requires participating countries to formally pledge that they will adopt the agreement within their own legal systems. The final step – known as “entering into force” – will happen when at least 55 countries, which together represent at least 55% of global emissions, adopt the agreement domestically. This last part is likely to take a few years.

A today’s ceremony, 155 countries are expected to sign the agreement.  This will set a new record for the number of signatories on an international accord. The previous record was held by the 1982 Montego Bay Law of the Sea agreement, which had 119 signatories.

Credit: UN

Credit: UN

Historic Deal Reached at UN Climate Change Conference in Paris

After decades of failed attempts, a global climate change agreement was reached at the  UN Climate Conference in Paris (COP 21) on Saturday. The deal, known as the Paris Agreement, marks the first time in history that all member nations agreed to reduce their greenhouse gas emissions in some way.

In the past, only developed economies like the US and EU were required to act while less developed economies like India and China were exempt. This was one of the major reasons why previous attempts to reach a worldwide climate agreement failed. The more universal approach used this time was largely attributed to, and builds on, last year’s bi-lateral climate pact between the US and China – the worlds two largest carbon polluters.

More than a year in the making, this hard won agreement has set the target of holding global warming to 2°C (3.6°F) above pre-industrial levels and urged countries to pursue an even tighter cap of 1.5°C (2.7°F) if possible. To achieve this goal, it employs a mix of voluntary and legally binding actions. While every country will follow their own emissions reduction plan, there is no requirement quantifying the amount of greenhouse gases they have cut or how it has to be done. Additionally, there are no penalties for those who do not live up to their promises. Based on the current collection of national plans, which vary widely in ambition, this agreement will only cut greenhouse gas emissions by about half of what is necessary to reach the 2°C (3.6°F) goal. But, the agreement does legally obligate countries to reconvene every five years to present updated plans spelling out how they will deepen their emissions cuts. It also requires countries to publically report how much emissions they have actually eliminated compared to their plans every five years starting in 2023.

The ultimate outcome of this historic deal will not be known for years to come, especially since it depends heavily on the tactic of “name and shame” and the hope that no country wants to be seen as a slacker in the eyes of the world. It is also deeply dependent on the actions of future government officials who will have to carry out these plans. That said, the global participation and overall spirit of the agreement is, without a doubt, a solid step in the right direction in terms of addressing climate change.  The Paris Agreement goes into effect in 2020.

COP 21 in Paris. Credit: Arc20

COP 21 in Paris. Credit: Arc2020

Deforestation and Climate Change

Today is Arbor Day, a holiday that celebrates the importance of trees. As such, it seems appropriate to talk about the role deforestation plays in global climate change.

According to the World Wildlife Federation, deforestation and forest degradation account for 15% of global anthropogenic carbon dioxide (CO2) emissions. That makes it the second largest human-generated source of carbon dioxide in the atmosphere, behind only the burning of fossil fuels.

Forests are often called the “lungs” of our planet, as trees absorb CO2 and release oxygen as part of the process of photosynthesis. As such, forests act as carbon sinks. When cut down, the trees not only stop absorbing CO2, but they release it when they are burned or left to decompose. The WWF says we lose forests around the globe at the rate of 36 football fields every minute.

Deforestation is the large scale clearing of forests for other land uses. Its biggest drivers are agriculture and logging. In the tropics, where trees grow year round, forests are often cleared to make way for monoculture farms of palm oil or soybeans. While these crops also absorb CO2, it is far less than the amount absorbed and stored by native forests.

Deforestation also has localized climate impacts. Without trees to evaporate ground water and release it as water vapor though the process of transpiration, local climates tend to get drier. When it does rain, runoff increases and accelerates the rate of soil erosion. Deforestation also means a loss of habitat for numerous species of plants and animals, which lends itself to a decrease in biodiversity.

Recognizing the scale at which deforestation is impacting global climate change, policymakers at the UN adopted a set of policies known as REDD (Reducing Emissions from Deforestation and Forest Degradation). They offer monetary incentives to governments in developing nations to maintain and manage their forests more sustainably.  In facing the challenges of climate change, mitigation efforts are needed on all fronts.

Modest Deal Reached at UN Climate Conference in Lima

After two weeks of negotiations, a global agreement – however modest – was reached at the UN Climate Change Conference in Lima, Peru this weekend.

The deal, known as the Lima Accord, marks the first time in history that all nations have agreed to reduce their rates of greenhouse gas emissions. Up until now, only developed nations had been required to act.  Since the UN first started holding climate change conferences in the mid-1990s, many of the larger less developed nations, including China, India, and Brazil, have become industrial powerhouses adding significant amounts of greenhouse gases to the atmosphere.  In fact, China is now the world’s largest carbon polluter.

Under the current agreement, every country will submit an “intended nationally determined contribution” or INDC.   These are essentially plans, due in the spring, in which individual countries spell out how much CO2 emissions they propose to cut after 2020 based on their own domestic economic and political situations. Collectively, these independent plans will form the framework for a global climate treaty set to be finalized at the UN Climate Conference in Paris late next year.

While this bottom-up approach helped secure the participation of all countries, it is not legally binding and leaves countries with the latitude to make as little a contribution as possible. That said, this new accord cuts through some of the historic blame game and recognizes climate change as a global problem that requires a global solution. The question is, will the proposed aggregate reductions in greenhouse gases be enough to meet the current international goal of limiting global warming to less than 2°C (3.6°F) above pre-industrial levels and stave off the worst impacts of climate change?

How Greenhouse Gases Influence Climate

The latest round of UN climate change talks is currently underway in Lima, Peru. Representatives from nearly 190 countries are meeting to discuss ways to reduce greenhouse gas emissions, the main driver of global warming.

Earth’s atmosphere is made up of a variety of gases, mostly nitrogen and oxygen by volume. The greenhouse gases, including water vapor, carbon dioxide, and methane, represent a smaller percentage, but are also a natural part of the mix. Acting like the windowpanes of a traditional glass greenhouse, these gases allow the sun’s energy (shortwave radiation) to pass through the atmosphere during the day and heat the Earth’s surface. At night, the greenhouse gases trap some of the heat (long-wave radiation) that the surface emits as it cools.  In essence, greenhouse gases function like a blanket that help keep the planet warm. Without them, the average surface temperature of the Earth would be 0°F – a temperature at which all the water on the planet would be frozen and life as we know it would not exist. Having too many greenhouse gases is also a problem – one that we are currently facing.

Simply put, more greenhouse gases in the atmosphere trap more heat and increase the planet’s average temperature. During the last century, according to the IPCC, Earth’s mean temperature rose 1.5°F.  As temperatures continue to rise, long established weather patterns and storm tracks are shifting. Different regions, in turn, are being affected in different ways. Some areas are getting wetter, while others are getting dryer, and coastal communities are feeling the impacts of rising sea levels.

Scientists say that while some greenhouse gases come from natural sources like volcanic eruptions, the vast majority entering our atmosphere today come from human activities that burn fossil fuels. Before the industrial revolution in the late 1700’s, atmospheric carbon dioxide levels were 280 parts-per-million (ppm). This year, it passed 400ppm for the first time in human history. In addition, according to NOAA, 2014 is on track to be the planet’s warmest year on record.

Any agreements reached in Lima on reducing greenhouse gas emissions will be used as the framework for a binding global treaty at the UN Climate Conference in Paris next year.

Source: dec.ny.gov

Source: dec.ny.gov

US and China Reach Climate Change Agreement

The United States and China have teamed up to tackle the pressing global issue of climate change. President Barack Obama and President Xi Jinping announced their ambitious bi-lateral agreement in a joint press conference on Wednesday in Beijing, where both leaders were attending the Asia Pacific Economic Cooperation (APEC) summit.

Under this historic agreement, the US will reduce its carbon emissions by 26% – 28% below its 2005 levels by 2025. China will cap its growing emissions by 2030, if not earlier, and increase its use of non-fossil fuels by 20% by the same year.

While ambitious, climate scientists say the amount of emission cuts laid out in this bi-lateral agreement alone will not be enough to meet the current global goal of limiting warming to less than 2°C (3.6°F) above pre-industrial levels. That said, it does clear the path for other nations to take similar actions.

China and the US are the world’s two largest economies and two largest carbon polluters. By acting together, President Obama said, “We hope to encourage all major economies to be ambitious – all countries, developing and developed – to work across some of the old divides, so we can conclude a strong global climate agreement next year.”

The first indications of whether this bi-lateral action will spur long stalled global climate negotiations will come this December at the next round of UN climate talks in Lima, Peru. After that, the big test will be the 2015 UN Climate Change Conference in Paris, where the objective is a binding global agreement to reduce greenhouse gas emissions. Any deal reached there will go into effect in 2020.