Fossil Fuels burning by humans have already warmed the planet by at least 1 degree Celsius that expel large quantities of heat-trapping gases into the sky. The sea levels are rising. Many deadly disasters like flooding, heatwaves, wildlife fires are causing lots of damage. The effects of climate change are faced worldwide. According to the latest report from IPCC, that much is “unequivocal.” Humans still have the power to slow the climate crisis.
The 1st report from the IPCC 6th assessment report focuses on the physical science behind climate change. It considers five scenarios of how humans will respond to global warming. According to IPCC, some of the extreme projections of the past will come true. Now the world needs to take rapid action on climate change, and whatever it has done to date lot more needs to be done. However, “Scenarios are not predictions,” the report says. “Instead, they provide a ‘what-if’ investigation of the implications of various developments and actions.”
How scientists are struggling with the unpredictable change of human behavior is shown by these scenarios. Depending on the human decision, Earth has many possible futures. These visions of tomorrow mean humans have changed the world, but the potential warming is still in the hands of humans.
IPCC five stories about climate change –
IPCC report has 4000 pages, and if a person reads the pages, then will come to know that there are five different stories about climate change, complete with their little narratives. The Earth is undergoing a massive, uncontrolled experiment. It also reveals what happens when 2.6 million pounds of carbon dioxide per second are added to the atmosphere.
The subjects are constantly messing with the control, so it is an immensely frustrating experiment. How more Earth will warm up depends upon what humans will do. And what people are doing is changing. One thing is clear that many factors that helped bring the world to the current point will not be seen in the future, like too few clean energy options, a massive surge in coal mining, unchecked population growth.
The countries agreed in this century to limit warming to less than 2°C, with an additional target of staying below 1.5°C with the 2015 Paris climate agreement. When the IPCC put out its last comprehensive report in 2013, these goalposts didn’t exist. The researchers better understand climate sensitivity with improvements in measurements, simulations, and historical climate studies. Climate sensitivity ranged between 1.5°C and 4.5°C for decades. Now the range between 2.5°C and 4°C has been set by the scientist, with 3°C as the most likely value.
The next step is to figure how much carbon dioxide will be emitted. To find out the amount of carbon dioxide emission, scientists have imagined how humans will progress. Scientists will consider the usage of clean energy, population growth, and an observer effect, in which to limit greenhouse effect alarming climate science comes into action. IPCC 5 stories are known as shared socioeconomic pathways (SSPs). Each makes different assumptions in terms of shifts in policy, economics, and technology.
The five stories –
- This is called “taking the green road.”
- It is the most complex and most ambitious storyline to achieve.
- It imagines a gradual but concerted shift toward clean energy. But there will be few political barriers adapting this for climate change.
- This believes that there will rapid reduction in fossil fuels, increasing energy efficiency, widespread use of clean energy, and lower resource demands.
- Humanity will zero out its contributions to climate change by the middle of the century.
- This scenario also assumes that there were will global development that will lift all countries.
- It imagines improvement in health and education that would help stabilize population growth, with the total declining slightly to 7 billion people.
- This scenario assumes that the world will act on climate change eventually, but more slowly than in the optimistic path of SSP1-1.9.
- After 2050, it assumes an economy with net-zero emissions.
- This expects the global population to reach 7 billion people.
- The results will be that the world will warm up to 1.8°C, with a likely range between 1.3°C and 2.4°C by 2100.
- This increase will cause sea levels will have risen between 30 and 54 centimeters by the end of the century, up from the 24 cm of growing that has already occurred. Another 10 million people around the world would be at risk from coastal flooding.
- A double number of people will be exposed to extreme heat in a world with 2°C of warming.
- More environmental declines and exposure to climate hazards with every bit of warming would bring.
- It is all about what countries have decided to do so far about climate change.
- If the existing obligations are fulfilled by every country, their emissions by 2100 will lead to about 2.7°C warmings, with a likely range between 2.1°C and 3.5°C.
- In the summer, the Arctic Ocean would likely be ice-free, which would have ripple effects on the weather worldwide.
- Scientists expect that 3 degrees C of warming would cause a significant drop in global food production, more devastating flooding from extreme rainfall, and far more extreme heat.
- From historical trends, future global development patterns will not radically shift.
- Inequalities will be there between countries, and development will be slow, but there will be international cooperation on environmental goals.
- The global population would peak at 9.6 billion people.
- In this, nationalism is resurgent, and countries withdraw from international cooperation. Countries focus on their own economic goals.
- In this scenario, countries will exploit their fossil fuels more.
- Investment in technological development and education would be reduced.
- In developing countries, population growth will remain high and stay low in industrialized countries, reaching 12.6 billion people.
- Working on climate change would become a less priority internationally.
- It accounts for high levels of heat-trapping gases other than carbon dioxide, including aerosols and methane.
- Sea level would have risen between 46 cm and 74 cm by the end of the century.
- Roughly by 3.6°C, the world will have warmed, with a range between 2.8°C and 4.6°C.
- This scenario imagines global economic growth across the board.
- There will be burning of coal, oil, and natural gas.
- The planet’s population is leveling off at 7 billion people.
- Resources will be adopted to climate change, but there will be little effort to make emissions less severe.
- The net result would be 4.4°C of warming, with a range between 3.3°C and 5.7°C.
Climate change and actions people can take –
If carbon dioxide emissions can be brought to zero today, carbon dioxide will not be warming, but that is impossible. Even the most aggressive climate action will not eliminate carbon emissions at once. It will take time. Till humans achieve zero carbon emissions, they can keep following this. To determine the long-term path, humans still have the power. Right now, the world is somewhere between scenarios 3 and 4.
Over the next 20 years, the five scenarios have been similar, with the average global temperature deviating from the standard by differing by less than one-tenth of a degree. These scenarios indicate how much of a challenge it will be for the world to change.