Category Environtal Studies

WHAT IS SEA LEVEL RISE AND WHY IS IT HAPPENING?

As our planet warms, oceans across the globe absorb a large portion of the heat generated. In the process, the water expands, resulting in universal sea-level rise. In addition, the rise is also caused by the melting of glaciers and icebergs. Usually such melting during warmer months and freezing during colder months is a natural phenomenon. However, with global warming, there’s more of the former than the latter, leading to alarming sea-level rise, threatening to submerge several cities within just a few decades.

Why does sea level change?

Causes sea level to rise because water expands as it warms up; melting of the world’s ice sheets. A large ice mass, which flows over hills and valleys and occupies a large portion of a continent. The world has only three major ice sheets today (Greenland, West Antarctica, and East Antarctica).

In Greenland and Antarctica;  melting of smaller around the world; and decrease in the amount of water held on land, for example, in groundwater beneath the land and in reservoirs above the land. Ocean warming accounts for around half of the observed change in sea level (this is often called “thermal expansion”), with the melting of thousands of small glaciers accounting for the other half of the increase in sea level. Since the 1800s, the melting ice sheets in Antarctica and Greenland have contributed relatively little to sea level change. But, these ice sheets are starting to melt faster due to global warming and may push sea level up much more in the future.

How much could sea level rise?

Because of global warming, the thermal expansion of the ocean and glacier melting will continue to play a role in the rise of sea level in the future . If all of the planet’s remaining as small glaciers were to melt, sea level would rise about 50 cm. The amount that thermal expansion can raise sea level in the future will depend on the continued warming of sea water. The largest possible contribution to sea level rise in the future comes from the world’s large ice sheets in Greenland, West Antarctica, and East Antarctica. If these ice sheets melted completely, the level of the oceans would rise about 7 m from the Greenland ice sheet, 5 m from the West Antarctic ice sheet, and 53 m from the East Antarctic ice sheet. This is why many glaciologists (scientists who study ice) focus on how Greenland and Antarctica are changing because of global warming.

How will sea level rise affect the countries of the world?

The effect of ice sheet melting on sea level is different across the world.

So, when the sea level rises, people will be affected in different ways, depending on where they live. The UK is used to occasionally dealing with rising sea level for short periods of time, particularly when there are storms at the same time as when the tides higher than usual. If the IPCC predictions are correct, we must consider the possible increase in sea level on top of natural tidal surges. This will cause dangerously high tides to occur more often in the coming decades, and these future tides might be more destructive than we are used to.

In farming regions near the coast, seawater flooding on land can contaminate the soils with salt, making them less able to support the growth of crops. The salty water may also get into underground stores of fresh water (known as groundwater), which is the source of important drinking water and also for farmers to grow crops.

In coastal cities, sea level rise will cause more flooding to houses, businesses, and while it may seem sensible to consider moving cities away from harmful floods, especially as we know it will likely happen in the future, our cities cost so much to develop that we are more likely to simply try to protect them from rising sea levels. A vision of our cities near the sea involves them with walls facing the ocean several meters high, with the street level of the cities themselves being below the level of the ever rising sea.

Credit : Frontiers for young mind 

Picture Credit : Google 

WHAT ARE SUSTAINABLE DEVELOPMENT GOALS?

Also known as Global Goals, these are 17 interconnected goals that aim for a better and sustainable future for everyone in the world. The goals were created by the United Nations General Assembly in 2015, and are hoped to be achieved by 2030. They cover a wide range of areas such as gender equality, hunger, education, innovation, green energy, good health, sustainable development, economic growth, peace, justice, etc. The goals also reflect how positive action in one area can impact others.

The 17 sustainable development goals (SDGs) to transform our world:

GOAL 1: No Poverty

GOAL 2: Zero Hunger

GOAL 3: Good Health and Well-being

GOAL 4: Quality Education

GOAL 5: Gender Equality

GOAL 6: Clean Water and Sanitation

GOAL 7: Affordable and Clean Energy

GOAL 8: Decent Work and Economic Growth

GOAL 9: Industry, Innovation and Infrastructure

GOAL 10: Reduced Inequality

GOAL 11: Sustainable Cities and Communities

GOAL 12: Responsible Consumption and Production

GOAL 13: Climate Action

GOAL 14: Life Below Water

GOAL 15: Life on Land

GOAL 16: Peace and Justice Strong Institutions

GOAL 17: Partnerships to achieve the Goal

The SDGs build on decades of work by countries and the UN, including the UN Department of Economic and Social Affairs:

  • In June 1992, at the Earth Summit in Rio de Janeiro, Brazil, more than 178 countries adopted Agenda 21, a comprehensive plan of action to build a global partnership for sustainable development to improve human lives and protect the environment.
  • Member States unanimously adopted the Millennium Declaration at the Millennium Summit in September 2000 at UN Headquarters in New York. The Summit led to the elaboration of eight Millennium Development Goals (MDGs) to reduce extreme poverty by 2015.
  • The Johannesburg Declaration on Sustainable Development and the Plan of Implementation, adopted at the World Summit on Sustainable Development in South Africa in 2002, reaffirmed the global community’s commitments to poverty eradication and the environment, and built on Agenda 21 and the Millennium Declaration by including more emphasis on multilateral partnerships.
  • At the United Nations Conference on Sustainable Development (Rio+20) in Rio de Janeiro, Brazil, in June 2012, Member States adopted the outcome document “The Future We Want” in which they decided, inter alia, to launch a process to develop a set of SDGs to build upon the MDGs and to establish the UN High-level Political Forum on Sustainable Development. The Rio +20 outcome also contained other measures for implementing sustainable development, including mandates for future programmes of work in development financing, small island developing states and more.
  • In 2013, the General Assembly set up a 30-member Open Working Group to develop a proposal on the SDGs.
  • In January 2015, the General Assembly began the negotiation process on the post-2015 development agenda. The process culminated in the subsequent adoption of the 2030 Agenda for Sustainable Development, with 17 SDGs at its core, at the UN Sustainable Development Summit in September 2015.
  • 2015 was a landmark year for multilateralism and international policy shaping, with the adoption of several major agreements:
  • Sendai Framework for Disaster Risk Reduction (March 2015)
  • Addis Ababa Action Agenda on Financing for Development (July 2015)
  • Transforming our world: the 2030 Agenda for Sustainable Development with its 17 SDGs was adopted at the UN Sustainable Development Summit in New York in September 2015.
  • Paris Agreement on Climate Change (December 2015)
  • Now, the annual High-level Political Forum on Sustainable Development serves as the central UN platform for the follow-up and review of the SDGs.

Today, the Division for Sustainable Development Goals (DSDG) in the United Nations Department of Economic and Social Affairs (UNDESA) provides substantive support and capacity-building for the SDGs and their related thematic issues, including water, energy, climate, oceans, urbanization, transport, science and technology, the Global Sustainable Development Report (GSDR), partnerships and Small Island Developing States. DSDG plays a key role in the evaluation of UN system wide implementation of the 2030 Agenda and on advocacy and outreach activities relating to the SDGs. In order to make the 2030 Agenda a reality, broad ownership of the SDGs must translate into a strong commitment by all stakeholders to implement the global goals. DSDG aims to help facilitate this engagement.

Credit : United nations 

Picture Credit : Google 

WHAT ARE RAINFORESTS?

Rainforests are regions that consist of several tall trees, most of which are evergreen ones, and receive a large quantity of rainfall. They play an important role in taking in carbon dioxide from the atmosphere, and so, are often referred to as the lungs of the planet. They host an impressive variety of wildlife, and also influence weather patterns elsewhere in the world. All continents except Antartica house rainforests. The Amazon in South America is the world’s largest rainforest.

Tropical rainforests are home to 80 percent of the world’s terrestrial biodiversity, all squeezed into a narrow strip of equatorial land. They are also home to millions of human beings that have been a part of forest ecosystem for thousands of years. While tropical rainforests are perhaps the most iconic, temperate rainforests are equally diverse and beautiful. Together, rainforests offer a gallery of the most beautiful, awe-inspiring places and creatures on Earth.

Since the beginning of history, humans have relied on rainforests, finding in them a steady supply of wood, plants, and animals, as well as fruits, fibers, grains, medicines, cloths, resins, pigments, and other materials. As millennia passed and many human communities moved farther away from the forest, our reliance on the forests did not weaken. Major trade routes, and even empires, developed to control the flow of the rainforest’s treasures.

Today, most of the industrialized world senses little connection to the rainforest, living in large, busy cities far away from these fertile ecological powerhouses. We forget that the forest regularly saves our global food supply by offering new, disease-resistant crops. We forget about the hundreds of billions of dollars worth of trade in timber, non-timber forest products and forest-derived pharmaceuticals. We forget about things that are ultimately beyond value: the livelihoods of millions of forest communities, a stable and livable climate for us all, the existence of most of our fellow species, and simple things we take for granted, like regular rain and clean air.

In tropical nations, many developing and debt-ridden, the forest is cleared in the hope of securing an economic future. Huge industrial interests—such as timber, agriculture, and mining—see an endless, profitable supply of cheap resources just waiting to be taken. Meanwhile, family farmers and loggers feel they have no option but to deforest in order to feed their families. However, innumerable studies and recent history show that little security can be found in tropical deforestation.

Thus far, our human family has erased half of our original endowment of rainforests. Our world is now facing a sixth mass extinction—the greatest extinction crisis since the fall of the dinosaurs 65 million years ago. The future of over half of Earth’s plants and animals—and hundreds of human cultures—will be determined within the next few decades. Since our lives are so dependent on the forest’s bounty, our future is at stake as well.

Credit : Rainforest aligns 

Picture Credit : Google 

WHAT IS PARTICULATE MATTER?

Particulate matter or refers particle pollution to the mixture of tiny solid and liquid particles-metals, chemicals, dust, spores, etc.-present in the air we breathe. Many of these particles are harmful to us humans. Not just that. Particulate matter pollution alters our environment by contributing to acid rain, changing weather patterns, global warming, etc.

Where does particle pollution come from?

Particle pollution can come from two different kinds of sources — primary or secondary. Primary sources cause particle pollution on their own. For example, wood stoves and forest fires are primary sources.

Secondary sources let off gases that can form particles. Power plants and coal fires are examples of secondary sources. Some other common sources of particle pollution can be either primary or secondary — for example, factories, cars and trucks, and construction sites.

Smoke from fires and emissions (releases) from power plants, industrial facilities, and cars and trucks contain PM2.5.

Particle Pollution and Your Health

Breathing in particle pollution can be harmful to your health. Coarse (bigger) particles, called PM10, can irritate your eyes, nose, and throat. Dust from roads, farms, dry riverbeds, construction sites, and mines are types of PM10.

Fine (smaller) particles, called PM2.5, are more dangerous because they can get into the deep parts of your lungs — or even into your blood.

How can particle pollution affect our health?

Particle pollution can affect anyone, but it bothers some people more than others. People most likely to experience health effects caused by particle pollution include:

  • People with heart or lung diseases (for example, asthma)
  • Older adults
  • Babies and children

Particle pollution has also been linked to:

  • Eye irritation
  • Lung and throat irritation
  • Trouble breathing
  • Lung cancer
  • Problems with babies at birth (for example, low birth weight)

Take Action

When particle pollution levels are high, take steps to limit the amount of air you breathe in while you’re outside. For example:

  • Think about spending more time indoors, where particle pollution levels are usually lower.
  • Choose easier outdoor activities (like walking instead of running) so you don’t breathe as hard.
  • Avoid busy roads and highways where PM is usually worse because of emissions from cars and trucks.

Credit : Centers of disease control and preventions 

Picture Credit : Google 

WHAT IS OCEAN ACIDIFICATION AND WHY IS IT A PROBLEM?

While the livelihoods of more than three billion people depend on oceanic resources, the ocean also provides a large fraction of the oxygen we breathe and absorbs greenhouse gases, mitigating their effects in the atmosphere. Playing a key role in the Earth’s climate and weather systems, as well as in the global carbon cycle, the ocean is an immeasurable force of nature. However, human activities have fundamentally altered the ocean’s chemical composition. Since the late 1980s, 95 per cent of open ocean surface water has become more acidic. Oceans absorb about 30 per cent of carbon dioxide (CO2) we produce, reducing the pH of seawater. This process is known as ocean acidification. With atmospheric CO2 levels 50 per cent above pre-industrial levels, the problem is getting worse.

What is pH and acidity?

pH is the measure of the acidity or basicity of a liquid solution. A solution’s pH represents the concentration of hydrogen ions (H+) and hydroxyl ions (OH-) on a scale of 0 to 14. Pure water has a pH of 7 and is neutral – neither acidic nor basic – with equal concentrations of H+ and OH?. A solution with a pH lower than 7 is acidic, while a solution with a pH greater than 7 is basic. The pH scale is logarithmic, so a decrease of one pH unit is a ten-fold increase in acidity.

The ocean is slightly basic. Prior to the Industrial Revolution of the 18th to 19th centuries, the ocean’s average pH was about 8.2. Today, the ocean’s average pH is 8.1. This means that the ocean today is about 30 per cent more acidic then in pre-industrial times. By 2100, the pH of the ocean could decrease to about 7.8, making the ocean 150 percent more acidic and affecting half of all marine life, according to the Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report.

What is the effect of a more acidic ocean?

Ocean acidification threatens marine ecosystems, which also affects populations who rely on the ocean as a source of income and diet. Over three billion people depend on marine and coastal biodiversity for their livelihoods.

For marine ecosystems, ocean acidification presents a two-fold challenge: higher acidity and lower availability of carbonate ions (CO32-). Calcifying organisms – such as oysters, crabs, sea urchins, lobsters and coral – need CO32- to build and maintain their shells and skeletons. Furthermore, studies suggest marine shells and skeletons may dissolve more easily as pH decreases. Scientists are studying the extent to which calcifying organisms are affected by acidification and how some organisms may be more sensitive than others.

Energy spent by marine organisms overcoming more acidic conditions may reduce the energy available for physiological processes, such as reproduction and growth, threatening the stability of food chains that would affect the ecosystem resilience and economic activities, such as fisheries and tourism.

Credit : International atomic energy agency

Picture Credit : Google 

WHAT IS OZONE LAYER AND ITS IMPORTANCE?

About 15 to 35 km above the Earth’s surface is gas called Ozone that surrounds the planet. This layer shields the Earth from the UV radiation from the sun However, pollution has caused this layer to thin exposing life on the planet to harmful radiation. The Montreal Protocol on Substances That Deplete the Ozone Layer (which was adopted on September 15, 1987) is an international treaty designed to protect the ozone layer from depletion by phasing out the production of a number of substances believed to be responsible for ozone depletion.

How is Ozone created?

When the sun’s rays split oxygen molecules into single atoms, Ozone is created in the atmosphere. These single atoms combine with nearby oxygen to form a three-oxygen molecule — Ozone.

Who discovered the Ozone Layer?

The Ozone Layer was discovered by the French physicists Charles Fabry and Henri Buisson in 1913.

Why is Ozone Layer important?

Ozone protects the Earth from harmful ultraviolet (UV) rays from the Sun. Without the Ozone layer in the atmosphere, life on Earth would be very difficult. Plants cannot live and grow in heavy ultraviolet radiation, nor can the planktons that serve as food for most of the ocean life. With a weakening of the Ozone Layer shield, humans would be more susceptible to skin cancer, cataracts and impaired immune systems.

Is Ozone harmful?

Ozone can both protect and harm the Earth — it all depends on where it resides. For instance, if Ozone is present in the stratosphere of the atmosphere, it will act as a shield. However, if it is in the troposphere (about 10 km from the Earth’s surface), Ozone is harmful. It is a pollutant that can cause damage to lung tissues and plants. Hence, an upset in the ozone balance can have serious consequences.

Disruption of Ozone Balance in the atmosphere

Since the 1970s scientists have observed human activities to be disrupting the ozone balance. Production of chlorine-containing chemicals, such as chlorofluorocarbons (CFCs), have added to depletion of the Ozone Layer.

What is ‘Ozone Layer depletion’?

Chemicals containing chlorine and bromine atoms are released in the atmosphere through human activities. These chemicals combine with certain weather conditions to cause reactions in the Ozone Layer, leading to ozone molecules getting destroyed. Depletion of the Ozone Layer occurs globally, but the severe depletion of the Ozone Layer over the Antarctic is often referred to as the ‘Ozone Hole’. Increased depletion has recently started occurring over the Arctic as well.

Credit : Business standard

Picture Credit : Google