MUMBAI: The city’s greenhouse gas emissions are expected to peak in 2030, with an annual output of 26.80 million tonnes of carbon dioxide equivalent (tCO2Eq) of greenhouse gas (GHG) emissions , according to an analysis by the World Resources Institute (India) for the Brihanmumbai Municipal Corporation (BMC) recently unveiled the Mumbai Climate Action Plan (MCAP).
According to Mehul Patel, program manager at WRI (India) and one of the authors of MCAP,
“After 2030, emissions are projected to show a year-over-year decline under MCAP’s ‘ambitious’ scenario. The peak of 26.80 million tCO2eq is relative to the city’s baseline emissions for 2019, which was 23.42 million tCO2eq.
Carbon dioxide equivalence is a measure that describes, for a particular mixture of greenhouse gases, the amount of CO2 that would have the same global warming potential (GWP) over a defined period of time.
In Mumbai specifically, 72% of the city’s greenhouse gas mix comes from the use of coal-fired electricity, piped natural gas (PNG), liquefied petroleum gas (LPG), coal, of firewood and kerosene in residential, commercial and industrial establishments. Another 20% came from the transportation sector and 8% from the waste sector, in 2019, according to MCAP analysis.
What this means in simpler terms is that in 2019 every inhabitant of Mumbai emitted around 1.8 tonnes of CO2eq greenhouse gases into the atmosphere largely through these three pathways, namely the energy consumption, transport and waste. The main sources of these emissions would respectively be thermal power plants (coal), exhaust gases, landfills and sewers which emit biogas.
“Someone who takes a lot of flights, drives a gas-guzzling car, keeps the air conditioner on all day and doesn’t separate trash will have a much higher carbon footprint than someone who travels by train and doesn’t not lead a very high-consumption lifestyle, but the cumulative emissions from all these activities within the boundaries of Greater Mumbai are expected to drop after 2030, the peak year,” Patel said.
Notably, in the draft MCAP, Mumbai’s 2019 baseline emissions totaled 34.3 million tCO2eq, a number significantly higher than both the revised emissions baseline and the projected peak. in the final version which was made public on March 13. It also reduced the city’s per capita carbon footprint from 2.67 to 1.8 tonnes per year.
“The baseline was revised because our draft projections did not take into account the proposed share of renewables in the power grid by 2030 and 2050, and the steps the BMC is already taking to control landfill emissions. After reviewing additional data relating to these parameters, the baseline estimate has been revised from approximately 34 million tonnes to 23 million tonnes,” Patel said.
Under MCAP’s “business as usual” scenario, without taking any action to mitigate emissions, Mumbai’s annual carbon footprint by 2050 is projected to reach 64.8 million tCO2e/year by 2050, increasing by 2. 7 times between 2019 and 2050, according to MCAP.
In the “Existing and Projected” scenario – which is the third outcome modeled by MCAP – Mumbai’s annual GHG emissions are projected to reach 33.31 tCO2eq in 2040 and 53.1 million tCO2eq by 2050. This scenario “takes into account the effects of existing or planned city actions alongside regional and national policies”, but is not sufficient to meet the 1.5°C targets of the Paris Agreement.
But the ‘ambitious’ scenario, which would see Mumbai ‘achieve an equitable warming scenario of 1.5C’, now forms the basis for various mitigation measures and city-level emission reduction targets. prescribed in MCAP.
“MCAP has an overall mitigation goal of achieving net zero emissions by 2050. The plan’s intermediate and long-term goals include a 30% decrease in emissions by 2030, a 44% reduction in by 2040 and a net zero reduction by 2050 relative to base year (2019) emissions,” the BMC said in a statement March 13 when the document was published.
However, as MCAP itself reveals, a true net-zero carbon footprint for the city is virtually impossible in that time frame. “In the ambitious scenario, emissions are expected to
reduce 27% by 2030 and 72% by 2050 from 2019 emission levels. This implies that the city will have a residual emission representing a 30% gap to reach the 2050 goal of net zero emissions,” the document says on page 84.
“This residual gap comes mainly from older buildings and informal living quarters in the city that are not very energy efficient, emissions from optional waste management and the use of LPG in households. unless there is a roadmap to retrofit older buildings and increase their energy efficiency, they will continue to emit GHGs,” Patel said.
However, experts fear that even this partial target could be “dangerously optimistic” in its hopes of achieving the goals of the Paris Agreement. MCAP assumes that 50% of Mumbai’s total grid electricity – which contributes around 72% of the city’s total GHG emissions – will come from renewable sources by 2030 and 90% by 2050. It also assumes that 96% of the electrification of cars, the recycling of 80% of paper and plastic waste, increasing the share of public transport from 32% to 42%, and 100% of the electrification of public buses, light trucks, three-wheelers and taxis – all by 2050, if not sooner.
Not everyone agrees. “These are unwarranted assumptions,” said Hussain Indorewala, a teacher and urban researcher at the Kamla Raheja Vidyanidhi Institute of Architecture. “MCAP, although billed as a ‘planning’ document, relies on many other institutions, from private industries to regulators, to achieve net zero goals. But that does not require them to do so. Moreover, this alone is not enough to avoid the worst effects of climate change in Mumbai.
Meanwhile, the city administration is also pushing ahead with projects such as underground tunnels, coastal roads and shipping links that are extremely emissions intensive, but whose impacts were not considered in the MCAP. . “The coastal route has been labeled as ‘unsuitable’ by the Intergovernmental Panel on Climate Change (IPCC, a United Nations body), but there is no mention of this in the plan,” said added Indorewala.
Experts have also criticized MCAP for its lack of transparency, in that it does not provide the calculations on which the emission reduction targets were set, making it difficult for citizens to independently validate the WRI India and BMC analysis.
Anjal Prakash, lead author of the IPCC Sixth Assessment Report, said: “Without an independent peer review of the methodology, MCAP leaves out some important nuances. On the one hand, if the baseline GHG emissions have been revised with a difference of 11 million tonnes, this must be explained transparently so that the public can have confidence in the figures.
The residual emissions gap of 30% projected in 2050 is also concerning. While advancements in technology, or carbon offsetting, may help address these issues in the future, Prakash said the gap is too big not to be expected these days.
“The Maharashtra government’s efforts to create a climate action plan for Mumbai is commendable. This sets a positive precedent for other states and policy makers. But presenting MCAP as a path to net zero when the emissions gap is almost a third of your baseline is a bit misleading,” Prakash said.
Sunil Godse, head of the BMC’s environmental wing, did not respond to repeated requests for comment.