Editorial 1: How to prevent disruptions by flood and extreme weather events
Recent Context:
- Recently, the frequent incident of urban flooding is observed in major cities of India due to intense and frequent rainfall during the monsoon season.
Global warming as one the reasons for intense rainfall:
- As global warming increases and local warming in our cities goes well beyond the 2oC guardrail, the intensity of climatic-impact drivers like too much or too little rain and heat will increase, as will the frequency and intensity of extreme weather.
- As the IPCC, and Indian Institute of Tropical Meteorology (IITM), has shown that it could grow exponentially, much faster than our current governance, planning and infrastructure systems are able to adapt to.
- It will lead to massive future disruptions across urban India – flooding, water scarcity and heatwaves that we need to prepare for and adapt to.
Cities are vulnerable to climate change impact and disasters:
- Climate impacts and risks like flooding are felt intensely in our cities. This is because they concentrate one-third of our people and two-third of our economic output in increasingly dense built-up areas, with poor water, sanitation, drainage and wastewater infrastructure that struggle to even deliver everyday basic services.
- Irrational land use and planning systems exacerbate these challenges and amplify the vulnerability of tens of millions who are forced to live in informal settlements and slums.
- Cities in sensitive regions along the coast, rivers and hills face even worse impacts, due to higher exposure and locational vulnerability.
- Because of these complex interacting factors, traditional siloed responses to the climate crisis are doomed to fail. Yet city and state administrators from Surat to Indore to Gorakhpur and Kochi have successfully implemented several commonsense climate adaptation and flood response measures
Steps need to be taken by cities administration to reduce the loss of life and limit economic and property losses
- Ensuring drainage exists and works ( A proper moon audit of monsoon season):
- Most urban civic bodies conduct a monsoon audit ahead of the season. This is to ensure that storm water drains, tanks and lakes exist and work, and they are not choked by construction debris, silt, garbage or blocked by encroachments.
- It is a complex task that needs planning all through the year and adequate financial and human resources, which are rarely a priority.
- If done well, this can reduce the impact of flooding, along with helping recharge groundwater and surface storage, when the rain arrives.
- The medium-term solution is the integration of drainage, water supply and wastewater systems to store the intense rain that may come over a short period as well as treat and recycle wastewater to ensure safe water and sanitation through the rest of the year. This will enable better services and limit waterborne diseases.
- It needs to ensure that our drainage systems have enough capacity to take the greater intensity of rain that will come with a changing climate.
- Therefore, there is need to improve basic infrastructure in large cities, through schemes like AMRUT but the pace is far behind the accelerating changes in rainfall and urban expansion.
- Improving roads:
- The expansion of our urban areas faster than planned drainage systems means that many roads effectively become stormwater drains.
- To reduce local flooding, there us need to improve the way city roads are built and repaired.
- Therefore, there is needs for effective infrastructure planning and coordination by all concerned agencies that has been demonstrated in many cities.
- Greening cities and using blue-green-grey infrastructure:
- As cities expand to become impervious concrete jungles, there is less place for water to percolate and flow.
- Conserving and protecting urban forests, wetlands, rivers and lakes are critical to addressing climate change-induced flooding, water scarcity and heat waves and improving livability.
- For over a century, East Kolkata’s wetlands have been an effective flood defence mechanism that help treat a large share of the city’s sewage, produce half of the city’s fresh vegetables, and provide livelihoods to one lakh people.
- Therefore, Practical nature-based blue-green-grey infrastructure such as these hold the key to climate adaptation for many Indian cities.
- Reducing flood vulnerability:
- India has the technological capacity to map all of its cities and towns, using high-resolution satellite and local topographical data to identify areas most prone to flooding.
- This will help in addressing the vulnerability of millions of people, who live along river banks, low-lying areas and unstable slopes, whose everyday lives are dislocated during extreme events.
- As a result it becomes much better at evacuation and protecting people’s lives but have a long way to go in enabling real community-based resilience.
- Improving early warning services:
- After a devastating series of urban floods in cities like Mumbai and Surat in the early 2000s, India has done well to improve its forecasting, early warning, and evacuation systems in many large cities.
- This has to be extended to most places that are at risk along with strengthening critical cellphone, power and water supply services so that they are resilient and can recover rapidly from extreme events.
Conclusion:
- Therefore, there is need to protect and prepare our cities for future flooding, drought and heat waves that will arrive at our doorsteps with climate change.
- The most effective way to do this is to ensure that all urban residents have access to basic environmental services: Water, sanitation, drainage and solid waste management.
- Along with it, steps need to be taken to reduce our collective vulnerability, improve public health and re-imagine our cities to have more forests, parks, wetlands and lakes that are not gobbled up by irrational and often illegal changes in land use and poorly regulated real estate interests.
- Finally, it’s time to accept that we live in a warming world, in which climate change is a harsh reality that all of us — poor or rich — need to adapt to.
Editorial 2: New in Chandrayaan-3: key upgrades that bring hope and confidence
Recent Context:
- Recently, India’s third Moon mission, Chandrayaan-3 took off from the Sriharikota launching range
- The mission hopes to put behind the failure of Chandrayaan-2 which had crashed on the lunar surface in 2019. Important improvements have been made in the design to ensure that another accident is avoided.
- While attempting a soft-landing on September 7, 2019, Chandrayaan-2 had failed to reduce its speed to the desired level in the final seconds of descent.
- Scientists later detected problems in both the software and the hardware in consequence, the software and hardware in Chandrayaan-3 have been equipped with several additional capabilities
About Chandrayaan-3 Mission:
- Chandrayaan-3 is a follow-on mission to Chandrayaan-2 to demonstrate end-to-end capability in safe landing and roving on the lunar surface. It consists of Lander and Rover configuration. It is launched by LVM3 from SDSC SHAR, Sriharikota.
- Lander payloads:
- Radio Anatomy of Moon Bound Hypersensitive ionosphere and Atmosphere (RAMBHA)
- Chandra’s Surface Thermo physical Experiment (ChaSTE)
- Instrument for Lunar Seismic Activity (ILSA)
- Laser Retroreflector Array (LRA) Rover:
- Alpha Particle X-Ray Spectrometer (APXS)
- Laser Induced Breakdown Spectroscope (LIBS) Propulsion Module:
- Spectro-polarimetry of Habitable Planet Earth (SHAPE)
- The mission objectives of Chandrayaan-3 are:
- To demonstrate Safe and Soft Landing on Lunar Surface
- To demonstrate Rover roving on the moon and
- To conduct in-situ scientific experiments
Lander of Chandrayaan-3 mission: Strengthened legs
- A Lander does not have wheels; it has stilts, or legs, which are supposed to touch down on the lunar surface, and then stabilise.
- Chandrayaan-2 lost control over its descent around 7.2 km from the surface of the Moon. Its communications system relayed data of the loss of control up to around 400 m above the surface. The Lander had slowed down to about 580 km/hr when it crashed.
- The legs of Chandrayaan-3 have been strengthened to ensure that it would be able to land, and stabilise, even at a speed of 3 m/sec, or 10.8 km/hour.’
- Of course, this would be of little use if Chandrayaan-3 is struck by a problem similar to the one that crashed Chandrayaan-2, but this can certainly avert many other kinds of troubles in case of a rough landing.
More fuel storage capacity (Bigger fuel tank)
- The Chandrayaan-3 Lander is carrying more fuel than Chandrayaan-2. This has been done to ensure that the Lander is able to make a last-minute change in its landing site, if it needs to.
- The Chandrayaan-2 Lander too had the ability to change its course if the onboard cameras detected a boulder, a crater, or any other lunar surface feature that would make the landing unstable. The extra fuel is meant to enhance this capability.
- The Chandrayaan-2 Lander too had the ability to change its course if the onboard cameras detected a boulder, a crater, or any other lunar surface feature that would make the landing unstable. The extra fuel is meant to enhance this capability.
Chandrayaan-3 will face the Sun:
- The Chandrayaan-3 Lander has solar panels on four sides, instead of only two in Chandrayaan-2. This is to ensure that the Lander continues to draw solar power, even if it lands in a wrong direction, or tumbles over. At least one or two of its sides would always be facing the Sun, and remain active.
More instruments
- Additional navigational and guidance instruments are on board Chandrayaan-3 to continuously monitor the Lander’s speed, and make the necessary corrections.
- This includes an instrument called Laser Doppler Velocimeter, which will fire laser beams to the lunar surface to calculate the Lander’s speed. New sensors and cameras have also been added.
Updated software
- The hazard detection and avoidance camera, and the processing algorithm have been upgraded. The navigation and guidance software has also been updated. Multiple layers of redundancies have been added to ensure that if one system does not work because of any reason, something else will.
Multiple stress tests
- The Lander has been subjected to multiple stress tests and experiments, including dropping it from helicopters. ISRO created several kinds of test beds at one of its facilities to simulate lunar landing conditions.
Conclusion:
- Chandrayaan-3 is followed up mission of Chandrayaan-2 mission which aims to demonstrate ISRO’s capabilities and advancement in space. Therefore, it will help in further space exploration programme of India
