Topic 31: Global warming

The costs and benefits of global warming will vary greatly from area to area. For (1)_________ climate change, the balance can be difficult to assess. But the larger the change in climate, (2)__________ more negative the consequences will become. Global warming will probably make life harder, not easier, for most people This is mainly because we have already built enormous infrastructure based on the climate we now have.

People in some temperate zones may (3)______ from milder winters, more abundant rainfall, and expanding crop production zones. But people in other areas will suffer from increased heat waves, coastal erosion, rising sea level more erratic rainfall, and droughts.

The crops, natural vegetation, and (4) ________ and wild animals (including seafood) that sustain people in a given area may be unable to adapt to local or regional changes in climate. The ranges of diseases and insect pests that are limited by temperature may expand, if other environmental conditions are also favorable.

In its summary report on the impacts of climate change, the Intergovernmental Panel on Climate Change stated, “(5)________ as a whole, the range of published evidence indicates that the net damage costs of climate change are likely to be significant and to increase over time.”

(Source: https://earthobservatory.nasa.gov)

Climate change, also called global warming, refers to the rise in average surface temperatures on Earth. An overwhelming scientific consensus maintains that climate change is due primarily to the human use of fossil fuels, which (1) __________ carbon dioxide and other greenhouse gases into the air. The gases trap heat within the atmosphere, which can have a range of effects on ecosystems, (2) __________ rising sea levels, severe weather events, and droughts that render landscapes more susceptible to wildfires.

While consensus among nearly all scientists, scientific organizations, and governments is (3)__________ climate change is happening and is caused by human activity, a small minority of voices questions the validity of such assertions and prefers to cast doubt on the preponderance of evidence. Climate change deniers often claim that recent changes (4) __________ to human activity can be seen as part of the natural variations in Earth’s climate and temperature, and that it is difficult or impossible to establish a direct connection between climate change and any single weather event, such as a hurricane. While the latter is generally true, decades of data and analysis support the reality of climate change and the human factor in this process. In any case, economists agree that acting to reduce fossil fuel emissions would be far less expensive than (5) __________ with the consequences of not doing so.

(http://www.takepart.com/flashcards/what-is-climate-change/index.html)

The leaves of most plants are green, because the leaves are full of chemicals which are that colour. The most important of these chemicals is called “chlorophyll” and it (1) __________ plants to make food so they can grow using water, air and light from the sun. this way that a plant makes food for itself is called “photosynthesis” and it is one of the most important processes taking place on the (2) __________ planet.

(3) __________ photosynthesis there would be no plants or people on Earth. Dinosaurs would not have been able to breathe and the air and oceans would be very different from those we have today. So the green chemical chlorophyll is really important. All leaves contain chlorophyll, but sometimes not all of the leaf has chlorophyll in it. Some leaves have green and white or green and yellow stripes or (4)______. Only the green bits have chlorophyll and only those bits can make food by photosynthesis.

If you’re really good at noticing things, you might have seen plants and trees with red or purple leaves – and the leaves are that colour all year round, not just in autumn. These leaves are still full of the important green chemical, chlorophyll, just like any other ordinary green leaf. (5) _________________, they also have lots of other chemicals that are red or purple – so much of them that they no longer look green. But deep down inside the leaves, the chlorophyll is still there and it’s still green.

(http://theconversation.com/curious-kids-why-are-leaves-green-86160)

Glaciers are melting, sea levels are rising, cloud forests are dying. More alarmingly, wildlife is scrambling to keep (1) ____. It’s becoming clear that humans have caused most of the past century’s warming by (2) ____ heat-trapping gases as we power our modern lives. Called greenhouse gases, their levels are higher now than in the last 650,000 years.

We call the result global warming, but it is causing a set of changes to the Earth’s climate, or long-term weather patterns, that varies from place to place. As the Earth spins each day, the new heat swirls with it, (3) ____ up moisture over the oceans, rising here, settling there. It’s changing the rhythms of climate that all living things have come to rely upon.

What will we do to slow this warming? How will we cope (4) ____ the changes we’ve already set into (5) ____? While we struggle to figure it all out, the face of the Earth as we know it-coasts, forests, farms and snow-capped mountains-hangs in the balance.

(https://www.nationalgeographic.com)

Lead researcher on the atlas, Dr Zoë Randle, said the northerly migration of species of moths and butterflies is a phenomenon observed in northern Europe in recent decades. She said moths are proof that human-made climate change is happening now. Great Britain has observed the arrival of new species too, such as the Clifden Nonpareil, Tree-lichen Beauty and Black-spotted Chestnut. The atlas records that 38 per cent of all moth species in Britain and Ireland have spread to other areas in the last 50 years, most as a result of global warming. The book lists 893 species in all and the scientists’ analysis of distribution records over the period 1970-2016 in particular showed that 31 per cent of 390 larger moth species decreased significantly in Britain.

Intensive agriculture has caused the decline of many moth species through the destruction of wildlife-rich habitats and use of fertilizers and pesticides. Widespread environmental pollution such as artificial light at night and chemicals in the air and soil, are altering plant and animal communities in ways that are still not fully understood. Human-made climate change has facilitated the spread of moths to new parts of Britain and Ireland that were formerly too cold, while at the same time posing a long-term risk to species found in cool and restricted habitats such as mountainsides.

The atlas is based on more than 25 million records sourced from Butterfly Conservation’s National Moth Recording Scheme and the Moths Ireland database. These date from the 18th century through to 2016, meaning this volume contains 275 years of moth-recording effort by the public. Dr Randle said the same system of comprehensive recording is not yet available in Ireland as it is in Britain, but anecdotally she believes the same patterns are emerging in Ireland.

(Source: https://www.irishtimes.com/)

A number of scientists are emphasizing the tremendous challenger that will soon be posed when the depletion of fossil fuel supplies coincides with an alarming increase in the global population. They highlight agriculture, which is heavily dependent not only on gasoline to fuel machinery but also on the petrochemicals without which today’s synthetic fertilizers and pesticides could not be manufactured. But for the latter two, crop yields would be only a fraction of what they are. To assume that an abundant source of renewable energy will be a panacea is to ignore these vital non-fuel uses of petrochemicals.

Then there is the challenge posed to the current levels of mobility. As a fuel, gasoline has an unrivalled portability compared to electricity, which requires bulky batteries, and hydrogen, which is notoriously difficult to store. Biofuels might seem like an alternative but the energy (currently in the form of fossil fuels) consumed when converting corn into bioethanol, for instance, greatly exceeds the output when the fuels is utilized. In any case, once the crisis in the food supply looms large it will not make sense to divert food crops to other uses.

There seems to be a widespread belief that the era of oil dependency is coming to an end. There is a widespread complacency resting on the assumption that the experts will come up with a technological remedy making for a completely pain-free transition. Scientists such as Walter Youngquist argue that tis assumption may be mistaken and that the remaining resources might only support half of the current global population. In his opinion, the absence of a realistic alternative to fossil fuels will mean, amongst other things, that the first priority will be to curb the demand for food.

(http://www.fullspace.digitalcounterrevolution.co.uk/ecpe-practice-read…)

The temperature of the earth is rising at nearly twice the rate it was 50 years ago. This rapid rate and pattern of warming, scientists have concluded, cannot be explained by natural cycles alone. The only way to explain the pattern is to include the effect of greenhouse gases (GHGs) emitted by humans.

To come to a conclusion on climate change, the United Nations formed a group of scientists called the Intergovernmental Panel on Climate Change, or IPCC. The IPCC meets every few years to review the latest scientific findings and write a report summarizing all that is known about global warming. Each report represents a consensus, or agreement, among hundreds of leading scientists.

One of the first things the IPCC learned is that there are several greenhouse gases responsible for warming, and humans emit them in a variety of ways. Most come from the combustion of fossil fuels in cars, factories and electricity production. The gas responsible for the most warming is carbon dioxide, also called CO2. Other contributors include methane released from landfills and agriculture, especially from the digestive systems of grazing animals, nitrous oxide from fertilizers, gases used for refrigeration and industrial processes, and the loss of forests that would otherwise store CO2.

Different greenhouse gases have very different heat-trapping abilities. Some of them can even trap more heat than CO2. A molecule of methane produces more than 20 times the warming of a molecule of CO2. Nitrous oxide is 300 times more powerful than CO2.

Other gases, such as chlorofluorocarbons, or CFCs, which have been banned in much of the world because they also degrade the ozone layer, have heat-trapping potential thousands of times greater than CO2. But because their concentrations are much lower than CO2, none of these gases adds as much warmth to the atmosphere as CO2 does.

In order to understand the effects of all the gases together, scientists tend to talk about all greenhouse gases in terms of the equivalent amount of CO2. Since 1990, yearly emissions have gone up by about 6 billion metric tons of “carbon dioxide equivalent” worldwide, more than a 20 percent increase.

(Source: https://www.nationalgeographic.com/)

As places transformed, so did the people. When researchers at Yale University and the University of Westminster studied what images people associated with climate change, they found a shift this decade. When they began their study in 2003, the majority of people surveyed thought of melting polar ice. By 2016, more and more people had weather top of mind.

Climate, to be clear, is not weather. It’s the difference between a trend and a one-off event. But with wetter storms and hotter summers unfolding over the course of the decade, people were making new connections between climate change and the weather. Seeing climate change through the lens of something they experience every day opens the door for people to see the weight of the issue over their own lives. “Americans are just beginning to connect the dots and to say, wait a second, what’s going on here,” says Anthony Leiserowitz, a lead author of the study and director of the Yale Program on Climate Change Communication. “There’s been this increasing dawning of awareness among many Americans that climate change is actually starting to harm people here and now.”

New renewable energy projects outpaced new fossil fuel installations in worldwide growth for the first time in 2015. In a pivotal moment for the whole planet, every country on Earth agreed to take on climate change when they adopted the Paris climate accord in 2015. That committed countries to reducing their greenhouse gas emissions enough to keep the Earth from warming beyond roughly 1.5 degrees Celsius above pre-industrial levels, a threshold that could be catastrophic for people and ecosystems if it’s crossed. It was the culmination of years of political wrangling. “It is rare to have the opportunity in a lifetime to change the world,” former French president François Hollande told delegates gathered on the final day of negotiations. “Seize it so that the planet can live on, so that humanity can live on.”

But cooperation, even when the health of the whole planet is on the line, can be a fragile, fleeting thing. After Donald Trump was elected president in 2016, he began the process of formally withdrawing the US from the Paris accord. One by one, Trump backtracked on existing federal efforts to cut down on pollution, too. The words “climate change” began disappearing from government websites and documents.

(Source: https://www.theverge.com/)

Globally we use more energy than ever before, and the demand is rapidly growing. Economic expansion of emerging market economies, population growth and our increasing use of energy-consuming devices are among the most important contributing factors.

About one-third of the radiation hitting Earth’s atmosphere is reflected back out into space by clouds, ice, snow, sand and other reflective surfaces. The other two-thirds is absorbed by the Earth’s surface and the atmosphere. As the land, oceans and atmosphere heat up, they re-emit energy as infrared thermal radiation, which passes through the atmosphere. Heat-trapping gases like carbon dioxide (CO2) absorb this infrared radiation and prevent it from dissipating into space, giving rise to what we know as the greenhouse effect. The accumulation of CO2 and other greenhouse gases in the atmosphere is the dominating driver of recent climate change. CO2 is estimated to be responsible for 64 % of man-made global warming. Other greenhouse gases are released in much smaller amounts but still contribute significantly to the overall warming effect, as they are much more potent heat-trapping gases than CO2.

The EU is taking action on many levels. One example is on fluorinated gases that are contributing less than CO2 but still a particular point of concern in addressing climate change. They are used in several types of products, such as in refrigeration, air-conditioning and heat pump equipment. While fluorinated gases are released into the atmosphere in smaller quantities than other greenhouse gases, they are extremely potent – they produce a warming effect 23 000 times greater than CO2. For this reason the EU has decided to control their use. The EU’s regulation on fluorinated greenhouse gases aims at cutting the Union’s emissions by two-thirds compared to 2014 levels.

Chemicals are not only part of the problem – they are also part of the solution. Sustainable energy sources like solar power rely on chemical innovation using, for example, nanomaterials. One of the main challenges with renewable energy is how to increase its viability with the help of energy storage solutions. For example, solar panels have the best conditions in the desert, but that is not where most people live. Windmills also produce power during the night, which is when our energy consumption is at its lowest. In other words, technologies to improve energy storage and transportation is one of the important areas of research where innovation is needed.

(Source: https://chemicalsinourlife.echa.europa.eu/)

Rains that are almost biblical, heat waves that don’t end - there’s been a change in the weather lately. What’s going on?

Extreme weather is an unusual weather event such as rainfall, a drought or a heat wave in the wrong place or at the wrong time. In theory, they are very rare. But these days, our TV screens are constantly showing such extreme weather events. Take just three news stories from 2010: 28 centimetres of rain fell on Rio de Janeiro in 24 hours, Nashville, USA, had 33 centimetres of rain in two days and there was record rainfall in Pakistan.

The effects of this kind of rainfall are dramatic and lethal. In Rio de Janeiro, landslides followed, burying hundreds of people. In Pakistan, the floods affected 20 million people. Meanwhile, other parts of the world suffer devastating droughts. Australia, Russia and East Africa have been hit in the last ten years. And then there are unexpected heat waves, such as in 2003 in Europe. That summer, 35,000 deaths were said to be heat-related.

Peter Miller, a National Geographic columnist, says what is happening to our weather is probably a mixture of numerous factors. On the one hand, the most important influences on weather events are natural cycles in the climate. Two of the most famous weather cycles, EI Nino and La Nina, originate in the Pacific Ocean. The heat from the warm ocean rises high into the atmosphere and affects weather all around the world. On the other hand, the temperature of the Earth’s oceans is slowly but steadily going up. And this is a result of human activity. We are producing greenhouse gases that trap heat in the Earth’s atmosphere. This heat warms up the atmosphere, land and oceans. Warmer oceans produce more water vapour - think of heating a pan of water in your kitchen. Turn up the heat, it produces steam more quickly. Satellite data tells us that the water vapour in the atmosphere has gone up by four percent in 25 years. This warm, wet air turns into the rain, storms, hurricanes and typhoons that we are increasingly experiencing.

Climate scientist, Michael Oppenheimer, says that we need to face the reality of climate change. And we also need to act now to save lives and money in the future.

(https://www.ngllife.com/wild-weather)