If global warming continues at its current rate and if countries fail to take unprecedented measures to curb the increase, temperatures are likely to rise by 1.5 degrees Celsius between 2030 and 2052, a United Nations panel said in a new report. The impacts and costs of 1.5 degrees Celsius of global warming will be much more than expected, the Intergovernmental Panel on Climate Change said in its “Special Report on Global Warming of 1.5°C” report released in Incheon in South Korea on Monday.

The report is seen as the scientific guide for policymakers on how to implement the 2015 Paris Agreement, which pledged to keep the temperature rise between 1.5°C and 2°C. As per the agreement, nations have to take action towards preventing global temperatures from rising by 2°C by 2100. However, the agreement calls on countries to pursue measures to cap the rise to 1.5°C.

According to the latest study, the half-degree difference can have a huge impact. “Limiting global warming to 1.5°C compared to 2°C is projected to reduce increases in ocean temperature as well as associated increases in ocean acidity and decreases in ocean oxygen levels,” the report said. “Consequently, limiting global warming to 1.5°C is projected to reduce risks to marine biodiversity, fisheries, and ecosystems, and their functions and services to humans, as illustrated by recent changes to Arctic sea ice and warm water coral reef ecosystems.”

The global temperature is currently 1°C warmer than pre-industrial levels. With global warming of 1.5, climate-related risks to health, food security, water supply and economic growth, among others, are expected to increase, and increase further with 2°C, the report said. “Limiting warming to 1.5°C, compared with 2°C, is projected to result in smaller net reductions in yields of maize, rice, wheat, and potentially other cereal crops, particularly in sub-Saharan Africa, Southeast Asia, and Central and South America,” it added.

The Indian government said the country is already facing the impacts of climate change. “India recognises climate change to be a real threat and we will do whatever we can in our own capacity,” Ministry of Environment’s Additional Secretary AK Mehta told the Hindustan Times. “Denying the reality of climate change is not going to help anyone. We will act like a responsible nation.”

Aromar Revi, an Indian author of the report, told NDTV that Bengaluru, Delhi and other Indian cities are already experiencing the urban heat islands. “People across the world, especially in India, and we can see that in very objective terms, are experiencing the impact of warming,” Revi said. “If you take Kedarnath at one end or what happened in Srinagar or Chennai, or recently in Kerala. And of course, the very severe drought conditions in many parts of the country. And what we don’t understand is that our ecosystems, on which we survive on land and in the oceans, are experiencing this more severely.”

According to the report, renewable energy would need to supply 70% to 85% of electricity by 2050, as against the current 25%.

Measures to limit global warming to 1.5°C would require far-reaching and rapid transitions in urban, infrastructure, energy and industrial systems, the IPCC said. Jim Skea, co-chair of the IPCC working group, told Reuters that limiting warming to 1.5°C is possible within the laws of chemistry and physics, but doing so would require unprecedented changes.

“The challenges from delayed actions to reduce greenhouse gas emissions include the risk of cost escalation, lock-in in carbon-emitting infrastructure, stranded assets, and reduced flexibility in future response options in the medium to long-term,” it added.