By Teodor Teofilov
A new report from the UN’s Intergovernmental Panel on Climate Change warns that the impacts of climate change are increasing and inevitable. More than 100 scientists from around the world put together the findings, which is the most extensive look to date of the effects of climate change on the environment.
The report outlines the damage that climate change has already done to our planet’s oceans and ice sheets and forecasts the future of these crucial parts of our climate system. The impacts of climate change are already visible from the top of mountain peaks to the depths of the ocean and they are palpable for every one of us.
The problems are here, now, says the report, they aren’t theoretical. Glaciers, polar ice caps and our oceans have absorbed so much extra heat from manmade global warming that the systems that our existence depends on are at stake.
“The open sea, the Arctic, the Antarctic and the high mountains may seem far away to many people,” said Hoesung Lee, Chair of the IPCC in a press release. “But we depend on them and are influenced by them directly and indirectly in many ways – for weather and climate, for food and water, for energy, trade, transport, recreation and tourism, for health and wellbeing, for culture and identity.”
“If we reduce emissions sharply, consequences for people and their livelihoods will still be challenging, but potentially more manageable for those who are most vulnerable,” Lee said. “We increase our ability to build resilience and there will be more benefits for sustainable development.”
Just recently, Italian authorities closed roads and ordered the evacuation of huts on the Italian side of Mont Blanc after warnings that a staggering 250,000 cubic meters, or 8.8 million cubic feet of ice could break away from the Planpincieux glacier.
The rising temperatures mean that the oceans will have less oxygen, which together with more heatwaves and increased acidification, will force fish to move away from the coast and create bigger deadzones — areas that cannot sustain life.
The marine heatwaves happen twice as often as they did only three decades ago and millions depend on glaciers for water.
According to the report, this will lead to the extinction of some species of fish. The US dietary guidelines recommend 8-12 ounces of seafood a week for a healthy diet. Internationally fish plays a vital role, providing nearly half of animal protein eaten in developing countries and is a main source of vitamins and minerals.
Currently more than 600 million people or around 10 percent of the world’s population lives in coastal areas that are less than 10 meters above sea level and nearly 2.4 billion or 40 percent live within 100 km (60 miles) of the coast. The coasts are going to bear the brunt of higher seas and stronger storms.
The challenges facing humanity are only going to get worse unless countries move fast to eliminate greenhouse gas emission. Quick, decisive and strong action could stall or even completely curb some of the worst consequences.
“The world’s ocean and cryosphere have been ‘taking the heat’ from climate change for decades, and consequences for nature and humanity are sweeping and severe,” said Ko Barrett, Vice-Chair of the IPCC in a statement. “The rapid changes to the ocean and the frozen parts of our planet are forcing people from coastal cities to remote Arctic communities to fundamentally alter their ways of life.”
“By understanding the causes of these changes and the resulting impacts, and by evaluating options that are available, we can strengthen our ability to adapt,” she said. “The Special Report on the Ocean and Cryosphere in a Changing Climate provides the knowledge that facilitates these kinds of decisions.”
A year of reports
The Paris climate agreement was ratified in 2015 with the goal for countries around the world to try and limit the planets warming to an average of 2 degrees Celsius (3.6 degrees Fahrenheit) above the pre-industrial levels. Another aim was the more ambitious goal of keeping global warming under 1.5 degrees Celsius (2.7 Fahrenheit).
The 2 degrees Celsius target was considered to be safe and world leaders said that keeping the temperature below that would result in great stresses on the economy, society and natural environments, but would curb the most devastating consequences. However, things have changed.
Scientists have made it clear that our planet has already warmed by about 1 degree Celsius and there is evidence from thousands of researchers that even the 1.5 degree warming could have devastating effects on the environment, society and the world economy.
In the past year the IPCC has prepared three special reports on specific topics. The first, which was released at the end of last year, warned that even a 1.5 degree increase in global temperature would have devastating consequences for our planet. The report stated that a 1.5 degree increase in global temperature compared to pre-industrial levels will lead to “warming of extreme temperatures in many regions, increases in frequency, intensity and/or amount of heavy precipitation in several regions, and an increase in intensity or frequency of droughts in some regions.”
The second report, which was published in August, showed the already seen impacts and the likely future of forests and lands. The IPCC stressed the importance of quickly and drastically changing the way the world manages land.
“Land plays an important role in the climate system,” said Jim Skea, Co-Chair of IPCC Working Group III, in a press release. “Agriculture, forestry and other types of land use account for 23% of human greenhouse gas emissions. At the same time natural land processes absorb carbon dioxide equivalent to almost a third of carbon dioxide emissions from fossil fuels and industry.”
When land is degraded, it is less productive and restricts what can be grown, reducing the soil’s ability to absorb carbon, the report said. This exacerbates climate change, while climate change in turn exacerbates land degradation in many different ways, creating a vicious loop.
The last report, on the oceans and cryosphere completes the trio that together offer a disturbing future, especially because it is becoming apparent that even the 2 degrees target will be nearly impossible to hit.
Although an estimated four million people worldwide took part in a global climate strike earlier in September, the world leaders gathered at the UN Climate Action Summit in New York on September 23 didn’t announce any major new commitments to solving the greenhouse gas problem.
Our future is at stake
Summarizing decades of research from scientists worldwide, the report focuses on two crucial parts of the climate system — our oceans and ice. Climate change has already had a significant impact on both.
According to the report, ocean warming has contributed to a “overall decrease in maximum catch potential,” which together with overfishing makes the reduction of fish worse.
Marine heatwaves — periods of extremely high ocean surface temperatures — have doubled from 1982 to 2016 and are lasting longer and becoming more intense because of climate change. The heatwaves are projected to increase in frequency, duration, extent and intensity and will be 20 times higher than pre-industrial levels and would happen 50 times more often if emissions continue to increase strongly.
This warming and changes in the ocean chemistry has already disrupted species throughout the food web. Our oceans have already absorbed more than 90 percent of the excess heat in the climate system and the report expects that by 2100, the ocean will take up two to four times more heat than between 1970 and today if global warming is limited to 2 degrees Celsius. This will jump to five to seven times more at higher emission rates.
The warming of the ocean reduces the mixing between water layers and the supply of oxygen and nutrients for marine life. A study earlier this year showed that the increased ocean temperature has led to a more than 4 percent global decline in sustainable catches.
The ocean has also become more acidic, because it has taken up between 20 and 30 percent of human-created carbon dioxide emissions since the 1980s and a continued absorption by 2100 will exacerbate the acidification
All of these together “are already affecting the distribution and abundance of marine life in coastal areas, in the open ocean and at the sea floor,” the report states. “Communities that depend highly on seafood may face risks to nutritional health and food security.”
The report summarizes that already about 30 percent of the world’s reefs are reaching their breaking point, and 60 percent are heavily threatened. The 1.5 degrees of warming will lead to 70 to 90 percent of reefs being in danger of collapse by 2100. At 2 degrees, it jumps to more than 99 percent.
Along with the damage to marine life, people that live in mountain regions are going to be increasingly exposed to changes in water availability. Glaciers, snow, ice and permafrost are declining and will continue to do so, which will increase hazards for people through landslides, avalanches, rockfalls and floods.
The report projects that smaller glaciers in Europe, eastern Africa, the tropical Andes and Indonesia will lose more than 80 percent of their current ice mass by 2100, under high emission scenarios. Currently glaciers cover 10 percent of the land area on Earth — over 15 million square km (5.8 million square miles) — and store about 69 percent of the world’s fresh water.
The retreat of glaciers will alter water availability and quality downstream with implications for many sectors, such as agriculture and hydropower.
“Changes in water availability will not just affect people in these high mountain regions, but also communities much further downstream,” said Panmao Zhai, Co-Chair of IPCC Working Group I in the press statement. “Limiting warming would help them adapt to changes in water supplies in mountain regions and beyond, and limit risks related to mountain hazards. Integrated water management and transboundary cooperation provides opportunities to address impacts of these changes in water resources.”
The retreating glaciers and the ice sheets in polar and mountain regions that are losing mass will contribute to an increase in sea levels. Global sea level has risen by 15 cm during the 20th century, but now it is rising more than twice as fast with 3.6 mm per year and this is process is accelerating, showed the report.
It is expected that the rise will continue for centuries and could reach 30-60 cm by 2100 even if we limit the global temperature rise to well below 2 degrees. If we keep our current rate the sea level will rise around 60 to 110 cm.
“In recent decades the rate of sea level rise has accelerated, due to growing water inputs from ice sheets in Greenland and Antarctica, in addition to the contribution of meltwater from glaciers and the expansion of warmer sea waters,” said Valérie Masson-Delmotte, Co-Chair of IPCC Working Group I, in the press release.
On Sept. 30 a 315 billion-tonne iceberg broke off Antarctica. The massive iceberg broke off of the Amery Ice Shelf and is the biggest iceberg that its produced in more than 50 years. The block of ice covers 1,636 square km (more than 630 square miles) in area and is a little smaller than Scotland’s Isle of Skye and bigger than the area of Los Angeles. The size of the iceberg means it will have to be monitored and tracked because it could pose a hazard to shipping in the future.
However, scientists said this is part of the shelf’s normal “calving,” or breaking cycle and they don’t think climate change played a role in the event. Despite large surface melts in the summer, the Amery Ice Shelf is doing relatively well compared to its surroundings.
Although the Amery Ice Shelf is doing relatively well, recent research found that sea ice levels in the Antarctic are at their lowest in 40 years. The study published in July in the journal Proceedings of the National Academy of Sciences found that between 2014 and 2017 Antarctica lost as much sea ice as the Arctic did in over 30 years.
The sea level rise will also increase the frequency of extreme events, which happen for example, during high tides and intense storms. The IPCC report states that every degree of additional rise in global temperature will increase the likelihood of events that happened once a century in the past to become a yearly occurrence by 2050, increasing the risk for low-lying coastal cities and small islands.
The report shows that without major investment in adaptation they would have increasing flood risks and some island nations can become uninhabitable, but it notes that habitability thresholds are extremely difficult to assess.
“Various adaptation approaches are already being implemented, often in response to flooding events, and the report highlights the diversity of options available for each context to develop integrated responses anticipating the full scale of future sea level rise,” said Masson-Delmotte.
Urgent action is needed
Reducing greenhouse emissions, protecting and restoring ecosystems and managing the use of natural resources will make it possible to preserve the ocean and cryosphere, limit risks to our livelihood and present us with many other societal benefits. This requires stronger action by governments worldwide and of the largest companies as just a 100 companies are responsible for 71 percent of global emissions.
“We will only be able to keep global warming to well below 2°C above pre-industrial levels if we effect unprecedented transitions in all aspects of society, including energy, land and ecosystems, urban and infrastructure as well as industry. The ambitious climate policies and emissions reductions required to deliver the Paris Agreement will also protect the ocean and cryosphere – and ultimately sustain all life on Earth,” said Debra Roberts, Co-Chair of IPCC Working Group II in a press statement.
The report shows that the future looks very different in a world where emissions drop quickly. It is also the first that underlines the importance of education to enhance climate change, ocean and cryosphere literacy.
“The more decisively and the earlier we act, the more able we will be to address unavoidable changes, manage risks, improve our lives and achieve sustainability for ecosystems and people around the world – today and in the future,” Roberts said.
The EU environment chief, Karmenu Vella, called the report “a wake-up call for the global community to tackle climate change.”