Mercury rising

A new report by researchers from Bangalore and Mumbai suggests that India could witness a two-degree and 4.8-degree rise in mean temperatures by 2030 and 2080 respectively, writes Madhumitha B

Sustainability has moved from being a choice to a necessity. If not, people all over the world will have to brace themselves to face more extreme weather conditions. And that’s not it. Droughts, floods, famines, pollution, natural disasters and health issues will all become the order of the day.

According to the latest national level report by researchers from Bangalore and Mumbai, there should be adequate planning to cope with or adapt to extreme rainfall and temperature projections rather than just average temperature projections.

This report, published in the latest edition of the Current Science, has Rajiv Kumar Chaturvedi, National Environment Fellow at the Indian Institute of Science (IISc) as the lead author. His IISc colleagues Professors N H Ravindranath, Mathangi Jayaraman and G Bala along with Jaideep Joshi of Indian Institute of Technology, Mumbai, were also part of the study. They have stated that India could potentially witness a two-degree and 4.8-degree rise in mean temperatures by the 2030s and the 2080s, respectively. This overall warming is an indicator of how extensively climate is projected to change in the coming years if we continue to disregard the emissions let out into the atmosphere.

That is not all. It also emphasises the severity of the change when it points to the fact that the number of days with extreme rainfall (8 cm/day) could increase by 60 per cent after 2050 and precipitation levels could rise anywhere between four and five per cent by 2030 and as much as six to 14 per cent before the end of the century. This recent research report has also gone a step further. It not only makes a bold projection of some key possibilities in the near future but also does not shy away from bringing to light the repercussions of lifestyles that have led to climate change. This is done using a new set of emission scenarios called Representative Concentration Pathways (RCPs) replacing older versions of climate models.

Updated climate model

Chaturvedi explains, “The IPCC (Intergovernmental Panel on Climate Change) published the special report on emission scenarios (SRES) in the year 2000 and the underlying economic and policy assumptions for these scenarios were fixed as early as 1997. 

Previous climate projections for India were based on these versions of the climate models that are now 15 years old. This is the first study for India that makes climate change projections based on the new RCP scenarios comprising 18 modelling groups and updated climate models.

This study clearly indicates the fallacy of relying on a single climate model for projections because the mean of 18 models had the best agreement with observations than any single model. It is comprehensive, a far more rigorous and reliable analysis in comparing the historical climate data with the model projections.”

Climate change is a highly deliberated subject across the world, even today. Some voices have it that warming and melting of ice in the Arctic region is merely a ruse to set a wave of hysteria into the atmosphere while also a convenient way to rake in the moolah. Not that they strongly reject any threat caused to the environment. They are of the opinion that the damage being caused to the planet may not be as severe as it is made out to be.Several scientists have shown otherwise.

The current analysis throws light on the steady change in the weather patterns over the many decades along with predictions that perceive the shift in the future atmosphere and its correlation with the degradation that is being caused everywhere.  According to Prof N H Ravindranath in this report titled ‘Multi-model climate change projections for India under representative concentration pathways’, “Warming of equal to or in excess to two degrees is considered ‘dangerous by the United Nations Framework Convention on Climate Change (UNFCCC) and the science community.

India is also a signatory to the Cancun Agreement to limit warming to less than two degrees. Our study finds that this threshold may be breached in India after 2030s and the all-India mean temperature rise could reach up to 4.8 degrees by 2080 if global CO2 emissions continue unabated.”

The 20C mark

In fact, the last few years have seen an enormous debate on this issue by several countries at international summits, but the actions that followed almost never met the enthusiasm reflected on the world platform. Climate change is recognised as the biggest challenge facing the planet.

The UNFCCC was adopted in May 1992 to primarily address the challenge of climate change. Agreements reached at the Conference of Parties (CoP) at UNFCCC recognised the need to hold the increase in global average temperature between 1.5°C and 2°C above pre-industrial levels.

The Current Science report cites another report which pointed out that “there was an indication that limiting warming to roughly two degree centigrade by the end of this century is unlikely since it requires an immediate ramp down of emissions followed by ongoing carbon sequestration in the second half of this century.”

Highlighting the predicament, this scientific paper makes a reference to the International Energy Agency which warns that the door of opportunity for limiting warming below two degree centigrades is fast closing.

Time for action

Without further action by 2017, all CO2 permitted for this stabilisation scenario will be locked in by existing power plants, factories and buildings, among others. Any significant change in altering these possible effects has to come in at the government level, at the local and national levels. Localised efforts to counter these changes can empower communities in bringing about a drastic difference.

Some of the most basic changes we could adopt include use of renewable based energy sources and energy-efficient practices.

Wastage of energy, electricity, water and heat should be avoided and energy efficiency practices should be promoted; deforestation and forest degradation should be checked and tree planting should be encouraged; sustainable and improved agriculture practices should be promoted and improved waste management practices should be promoted.

Climate report for India

*Northern India, particularly states of Rajasthan, Madhya Pradesh, Uttar Pradesh, Uttaranchal, Himachal, Delhi, Punjab and Haryana are projected to experience higher levels of warming than the rest of the country. In the North East, Arunachal Pradesh is projected to experience relatively higher levels of warming.'

*Rajasthan, Uttar Pradesh, Punjab, Madhya Pradesh and Haryana already experience very high temperatures during summer – projected higher warming in these regions will further exacerbate the heat stress in regions.

*Parts of Jammu and Kashmir is projected to experience the highest mean warming up to 8 deg C by 2080s (compared to 4.8 deg C for all India average).

*Himalayan regions are projected to experience the highest levels of warming. This clearly is a matter of concern for the precious Himalayan glaciers that feed India’s        major rivers and upon which millions of people in Northern India depend for their livelihoods and drinking water requirements.