TEMPERATURE RISE

 Introduction

Over the last 50 years, human activities – particularly the burning of fossil fuels – have released sufficient quantities of carbon dioxide and other greenhouse gases to trap additional heat in the lower atmosphere and affect the global climate.

In the last 130 years, the world has warmed by approximately 0.85oC. Each of the last 3 decades has been successively warmer than any preceding decade since 1850

 The planet is warming, from North Pole to South Pole.  And the impacts of rising temperatures aren’t waiting for some far-flung future–the effects of global warming are appearing right now. The heat is melting glaciers and sea ice, shifting precipitation patterns, and setting animals on the move. Sea levels are rising, glaciers are melting and precipitation patterns are changing. Extreme weather events are becoming more intense and frequent.

The Past & The Future

The 10 warmest years on record have all occurred since 2005, and 7 of the 10 have occurred just since 2014. Looking back to 1988, a pattern emerges: except for 2011, as each new year is added to the historical record, it becomes one of the top 10 warmest on record at that time, but it is ultimately replaced as the “top ten” window shifts forward in time.

By 2020, models project that global surface temperature will be more than 0.5°C (0.9°F) warmer than the 1986-2005 average, regardless of which carbon dioxide emissions pathway the world follows. This similarity in temperatures regardless of total emissions is a short-term phenomenon: it reflects the tremendous inertia of Earth's vast oceans. The high heat capacity of water means that ocean temperature doesn't react instantly to the increased heat being trapped by greenhouse gases. By 2030, however, the heating imbalance caused by greenhouse gases begins to overcome the oceans' thermal inertia, and projected temperature pathways begin to diverge, with unchecked carbon dioxide emissions likely leading to several additional degrees of warming by the end of the century.

" 2019 among the three warmest years on record" 

Many characteristics of climate change directly depend on the level of global warming, but what people experience is often very different to the global average. For example, warming over land is larger than the global average, and it is more than twice as high in the Arctic.

But it is not just about temperature. Climate change is bringing multiple different changes in different regions – which will all increase with further warming. These include changes to wetness and dryness, to winds, snow and ice, coastal areas and oceans. For example:

• Climate change is intensifying the water cycle. This brings more intense rainfall and associated flooding, as well as more intense drought in many regions.
• Climate change is affecting rainfall patterns. In high latitudes, precipitation is likely to increase, while it is projected to decrease over large parts of the subtropics. Changes to monsoon precipitation are expected, which will vary by region.
• Coastal areas will see continued sea level rise throughout the 21st century, contributing to more frequent and severe coastal flooding in low-lying areas and coastal erosion. Extreme sea level events that previously occurred once in 100 years could happen every year by the end of this century.
• Further warming will amplify permafrost thawing, and the loss of seasonal snow cover, melting of glaciers and ice sheets, and loss of summer Arctic sea ice.
• Changes to the ocean, including warming, more frequent marine heatwaves, ocean acidification, and reduced oxygen levels have been clearly linked to human influence. These changes affect both ocean ecosystems and the people that rely on them, and they will continue throughout at least the rest of this century.
• For cities, some aspects of climate change may be amplified, including heat (since urban areas are usually warmer than their surroundings), flooding from heavy precipitation events and sea level rise in coastal cities.

Impact of Temperature Rise 

• Ice is melting worldwide, especially at the Earth’s poles. This includes mountain glaciers, ice sheets covering West Antarctica and Greenland, and Arctic sea ice. In Montana's Glacier National Park the number of glaciers has declined to fewer than 30 from more than 150 in 1910.
• Much of this melting ice contributes to sea-level rise. Global sea levels are rising 0.13 inches (3.2 millimeters) a year, and the rise is occurring at a faster rate in recent years.
• Rising temperatures are affecting wildlife and their habitats. Vanishing ice has challenged species such as the Adélie penguin in Antarctica, where some populations on the western peninsula have collapsed by 90 percent or more.
• As temperatures change, many species are on the move. Some butterflies, foxes, and alpine plants have migrated farther north or to higher, cooler areas.
• Precipitation (rain and snowfall) has increased across the globe, on average. Yet some regions are experiencing more severe drought, increasing the risk of wildfires, lost crops, and drinking water shortages.
• Some species—including mosquitoes, ticks, jellyfish, and crop pests—are thriving. Booming populations of bark beetles that feed on spruce and pine trees, for example, have devastated millions of forested acres in the U.S.

Other effects could take place later this century, if warming continues. These include:

• Sea levels are expected to rise between 10 and 32 inches (26 and 82 centimeters) or higher by the end of the century.
• Hurricanes and other storms are likely to become stronger. Floods and droughts will become more common. Large parts of the U.S., for example, face a higher risk of decades-long "megadroughts" by 2100.
• Less freshwater will be available, since glaciers store about three-quarters of the world's freshwater.
• Some diseases will spread, such as mosquito-borne malaria (and the 2016 resurgence of the Zika virus).
• Ecosystems will continue to change: Some species will move farther north or become more successful; others, such as polar bears, won’t be able to adapt and could become extinct.

REFERENCES: 

• USGCRP, 2017: Climate Science Special Report: Fourth National Climate Assessment, Volume I [Wuebbles, D.J., D.W. Fahey, K.A. Hibbard, D.J. Dokken, B.C. Stewart, and T.K. Maycock (eds.)]. U.S. Global Change Research Program, Washington, DC, USA, 470 pp., doi: 10.7930/J0J964J6.
• NOAA National Centers for Environmental Information, State of the Climate: Global Climate Report for Annual 2020, online January 2021, retrieved on March 15, 2021 from https://www.ncdc.noaa.gov/sotc/global/202013.
•  IPCC, 2014: Summary for Policymakers. In: Climate Change 2014: Mitigation of Climate Change.
• who.int/
• https://www.nationalgeographic.com/
• https://www.ipcc.ch/

CAUSES OF CLIMATE CHANGE

Geological records show that there have been a number of large variations in the Earth’s climate. These have been caused by many natural factors, including changes in the sun, emissions from volcanoes, variations in Earth’s orbit and levels of carbon dioxide (CO2).

Global climate change has typically occurred very slowly, over thousands or millions of years. However, research shows that the current climate is changing more rapidly than shown in geological records.

The mechanics of the earth’s climate system are simple. When energy from the sun is reflected off the earth and back into space (mostly by clouds and ice), or when the earth’s atmosphere releases energy, the planet cools. When the earth absorbs the sun’s energy, or when atmospheric gases prevent heat released by the earth from radiating into space (the greenhouse effect), the planet warms.

 A variety of factors, both natural and human, can influence the earth’s climate system.

The main driver of climate change is the greenhouse effect. The greenhouse effect is a natural process that warms the Earth’s surface. When the Sun’s energy reaches the Earth’s atmosphere, some of it is reflected back to space and the rest is absorbed and re-radiated by greenhouse gases.

Some gases in the Earth's atmosphere act a bit like the glass in a greenhouse, trapping the sun's heat and stopping it from leaking back into space and causing global warming.

Many of these greenhouse gases occur naturally, but human activity is increasing the concentrations of some of them in the atmosphere, in particular:

• carbon dioxide (CO2)
• methane
• nitrous oxide
• fluorinated gases

NATURAL CAUSES

• Sun's Intensity
• Volcanic Eruptions 
• Changes in Earth's Orbit, Axial Tilt & Precession 
• Quality of Greenhouse Gases in the Atmosphere
• Ocean Currents 
• Changes in Land Cover
• Meteorites Impact

CAUSES FOR RISING EMISSIONS ( HUMAN INDUCED) 

• Burning coal, oil and gas produces carbon dioxide and nitrous oxide.
• Cutting down forests (deforestation). Trees help to regulate the climate by absorbing CO2 from the atmosphere. When they are cut down, that beneficial effect is lost and the carbon stored in the trees is released into the atmosphere, adding to the greenhouse effect.
• Increasing livestock farming. Cows and sheep produce large amounts of methane when they digest their food.
• Fertilizers containing nitrogen produce nitrous oxide emissions.
• Fluorinated gases are emitted from equipment and products that use these gases. Such emissions have a very strong warming effect, up to 23 000 times greater than CO2.

Thank you to all those who responded to our question on our social media platforms. Here are some of the answers we got as being causes of climate change: 

eaglewingorganization (Instagram)-

"Human activities are the leading causes of climate change...from deforestation to make a living, improper use of fertilisers especially those containing nitrogen, burning coal and use of gas emitting devices."

earthlab (Instagram) -

"Climate change is a combination of natural factors and human activities."

Amina Shah (Whatsapp)- 

"Our own actions. We burn the forest and we don't plant back, we create a lot of plastic items, we manufacture harsh chemicals which in turn affect the lands and the oceans, the list is endless." 

https://linktr.ee/theseedoflifefoundation

REASONS / CAUSES OF EXTINCTION

 In this chapter we shall brush through some of the causes or reasons of extinction. In our next chapter however, we shall look at the human induced causes in depth. 

1. Habitat Loss 

The most common cause of endangerment is habitat loss. Plants and animals need space to live and energy provided by food, just as humans do. As human population and consumption increase, wildlife habitat is converted to houses and highways. Forests are cut down for building materials, fuel, and paper.

Even if habitat is not completely destroyed, it can be fragmented or degraded so much that it can no longer support the species it once did.

Many species, particularly large mammals, need large areas of habitat to survive and reproduce. Patches of forest or grassland surrounded by farms or cities, or divided by roads, will not support these species. 

2. Changes in the Atmosphere 

We know little about how changes in our atmosphere, such as global warming or ozone depletion, is affecting other life forms. However it is becoming more apparent every day that climate change is, and will have a significant impact on the planets species.

3. Diseases 

Disease and insect infestations, which are natural and nonthreatening phenomena in many ecosystems, can deal a death blow to populations weakened or depleted by other pressures.

4. Climatic Heating and Cooling

Climate Change is caused by a number of things. The effect that climate has on extinction is very big. The biodiverse Earth can't keep up with the rapid changes in temperature and climate. The species are not used to severe weather conditions and long seasons, or a changing chemical make-up of their surroundings. As more species die, it is only making it more difficult for the survivors to find food. The warmer climates we are used to present-day are perfect for diseases and epidemics to thrive.

5. Changes in the Sea levels of Currents 

The changes in sea levels and currents is a result, in part, of the melting freshwater. The denser, saltier water sinks and forms the currents that marine life depends on. Ocean floor spreading and rising also affects sea level. A small rise in the ocean floor can displace a lot of water onto land that is all ready occupied. The gases from the volcanic activity can also be absorbed by the water, thus changing the chemical composition, making it unsuitable for some life.

6. Asteroids/ Cosmic Radiation 

Asteroids hit the earth with extreme force. The reverberations can be felt around the world. The impact site is completely destroyed.

Cosmic Radiation is radiation being emitted from outer space and the Sun. It is hypothesized that being exposed to too much cosmic radiation can mutate genes, which can potentially weaken a species' genepool in the future. Since the radiation comes from space and the Sun, it is extremely difficult to avoid the radiation. Supernova remnants is one source of cosmic radiation.

7. Acid Rain 

Acid rain forms when sulfur dioxide and/or nitrogen oxides are put out into the atmosphere. The chemicals get absorbed by water droplets in the clouds, and eventually fall to the earth as acid precipitation. Acid rain increases the acidity of the soil which affects plant life. It can also disturb rivers and lakes to a possibly lethal level.