A major initiative in the war on climate change taken by Bengaluru-headquartered Indian Space Research Organisation (ISRO) has led to all major global space agencies rushing to develop satellites that will monitor carbon emissions from each country – all…except ISRO itself. It was ISRO chairman AS Kiran Kumar, along with French National Centre for Space Studies (CNES) president Jean-Yves Le Gall, who took the lead in getting all heads of space agencies together for a meeting on the sidelines of the Asia- Pacific Remote Sensing Symposium.The symposium was jointly organised by ISRO, the Union ministry of earth sciences and the International Society for Optics and Photonics (SPIE) and held from April 3 to 7 in New Delhi. The decision to launch carbon and greenhouse gasmonitoring satellites was taken at the meeting that followed a session on ‘Roadmap to space-based earth observations & applications’ at the symposium.The clarion call was for utilising satellites for coordinated space-based monitoring of carbon emissions by each country – and hence find which country is the most-polluting. Following the New Delhi meet, other major space agencies officially announced plans to develop and launch satellites to monitor carbon emissions.As per the plans, TanSat, the first Chinese mini-satellite monitoring carbon dioxide; of Japan Aerospace Exploration Agency’s (JAXA) Greenhouse gases Observing Satellite-2 (GOSAT-2); Nasa’s Orbiting Carbon Observatory-3 (OCO-3); MERLIN (Methane Remote Sensing Lidar Mission), jointly developed by German Aerospace Centre (DLR) and French CNES; S5P and S5 in the EU’s Copernicus program of European Union with the European Space Agency (ESA); and CNES’s MicroCarb, are already under development to be launched later this year or early next year. But when Bangalore Mirror sought details about what kind of a satellite would be launched by ISRO, and when, the country’s premier space agency’s official one-line response was: “There is no satellite planned in the near future for carbon footprint monitoring.”Prof J Srinivasan, chairman, Divecha Centre for Climate Change (DCCC), in the Indian Institute of Science, informed BM that measuring carbon emissions from space alone is extremely difficult, unless space-based measurements are compared and analysed with groundbased and airborne ones. “Measurements have to be taken on the ground and from airborne sources too, because these measurements will have to include the carbon absorbed and emitted by plants, too,” he said, adding that plainly measuring carbon emission from space would be “next to impossible”.Srinivasan said: “That [measuring carbon emissions from space] is not going to happen so soon. It may happen only in the future, say, 10 to 20 years down the line.” However, technologically, other space agencies seem to have worked it out. For instance, official information on China’s TanSat says the satellite is planned to test space-based carbon measurements with those from six ground stations, including one in Beijing.Similarly, Nasa’s OCO-3 – which will be installed on the Japanese Experiment Module-Exposed Facility (JEM-EF) on the International Space Station (ISS) from where it will operate – will gather carbon measurements over sites where ground-based and airborne instruments will also measure carbon emissions.The urgency looming over India is evident. India was the last of the major economies to file its climate action plan before the UN Climate secretariat on October 1, 2015, in Bonn, Germany, detailing its goals and submitting the Intended Nationally Determined Contributions (INDCs) – a target plan of each country for reduction of greenhouse gases, signed at the United Nations Framework Convention on Climate Change (UNFCCC).India pledged carbon emission reductions from 33 per cent to 35 per cent per unit of its Gross Domestic Product (GDP) by 2030, with 2005 as the base level. This included a target of 40 per cent of power generation from non-fossil fuel-based sources like solar and wind energy sources by 2030.