Nature-based solutions for Cooling the Earth

The manage, protect, and restore ecosystems strategy is gaining ground and is widely viewed as a win-win strategy for addressing two of this century’s biggest global challenges: climate change and biodiversity loss. Yet the potential contribution of such nature-based solutions to mitigating climate change holds great promise. Policymakers and decision-makers urgently need to know: what role do nature-based solutions have in the race to net-zero emissions and stop further global temperature increases?

Land-use changes will continue to act long past the point at which net-zero emissions are achieved and global temperatures peak (known as peak warming), and will have an important role in planetary cooling in the second half of this century. Before then, nature-based solutions can provide real but limited mitigation benefits. Temperature is one of the three major influences on global patterns of plant growth. Along with available sunlight and water, temperature determines whether the land will support dense forests, grassland, or nearly barren desert. Conversely, plants influence how hot the surface of the land can become. In areas where vegetation is dense, the land surface temperature never rises above 35 degrees Celsius. Climate change is changing the phenology of tropical evergreen, semi-evergreen, moist deciduous, and dry-deciduous forests of India. The sequestration process of carbon thus alters land surface warming/cooling. The five-decade climate data along with vegetation phenology over India is changing – the greening period is reducing and the senescence phase is increasing. The sapping of soil moisture due to climate change-induced warming is one of the important factors of change in phenology.

Nature-based solutions in agriculture can also help with climate change adaptation and building resilience in communities. However, nature-based solutions alone are not enough to solve climate change. They also need to be combined with rapid cuts to greenhouse gas emissions and engineered forms of carbon removal. Restoring soil: Regenerative agriculture practices like crop rotation, cover crops, and no-tillage can help restore soil and prevent erosion. This can also help absorb more emissions.

1. Integrating trees with crops: Agroforestry is a practice that integrates trees with crops and pasture lands. This can increase carbon storage and create a canopy to regulate temperature and humidity;
2. Reducing livestock emissions: Less intensive livestock rearing can reduce emissions of methane, a greenhouse gas;
3. Reducing pesticide use: Reducing the use of pesticides can help reduce greenhouse gas emissions;
4. Conserving coastal wetlands: Coastal wetlands like mangroves, salt marshes, and seagrass beds trap organic matter in the soil and prevent it from entering the atmosphere;
5. Restoring native forests: Restoring native forests can act as a carbon sink; and
6. Paying farmers not to cut down forests: Paying farmers not to cut down forests can help preserve ecosystem services like carbon sequestration.

United Nations Environment Program (UNEP) and the Cool Coalition?launched the Nature for Cool Cities Challenge to encourage cities to use nature-based solutions to cool their cities.? World recently experienced a 13-month streak of record-breaking global temperatures and as blistering heat waves punish communities across several continents, 2024 is on track to be the hottest year on record. Global average temperatures are now perilously close to exceeding 1.5 degrees C (2.7 degrees F) above pre-industrial levels, a threshold scientists warn will bring increasingly dangerous droughts, wildfires, and other impacts of climate change. The cooling effect of Urban Green Space (UGS) can also be achieved by Nature-Based Solution (NBS) for the mitigation of urban heat. The approaches could be:

1. Vegetative shading and reduction of evapotranspiration are critical aspects of the UGS cooling and reduce energy consumption;
2. Spatial patterns of green patches and the reflection mechanism also play an equivalent role in this regard;
3. UGS-based NBS approaches can be applied to improve the cooling performance in and across urban areas; and
4. Scientific approaches advocate high-resolution UHI and green data in time and space.

About the greening of India's main task is to Restore, Conserve, and Protect Forest and Tree Cover for NDC Implementation in India (RECAP4NDC) is one of the National Mission for Green India (GIM) is one of the eight missions outlined under the National Action Plan on Climate Change. While greening it is advocated to account for Nature’s Contributions to People (NCP) and the distributional equity of NCP from forest restoration strategies. The approach suggests forest restoration areas across India with systematic conservation planning to assess the trade-offs between three NCPs:

1. Climate?change?mitigation?NCP,
2. Biodiversity?value?NCP?(habitat?created?for?forest-dependent?mammals),?and
3. Societal?NCP?(for?livelihoods,?housing?construction, material,?and?energy).

Integrated?plans?deliver?NCP?more?evenly?across?the?restoration?area, about 38-40 % of the population impacted belongs?to?socioeconomically?disadvantaged?groups,?greater?than their?overall?representation?in?India’s?population.?

Crucially, the more ambitious the climate target, the shorter the time frame for such solutions to affect peak warming. In other words, nature-based solutions must be designed for longevity. This means paying closer attention to their long-term carbon-sink potential, as well as their impacts on biodiversity, equity, and sustainable development goals. It also means continuing to limit global warming through other methods, from decarbonization to geological storage of carbon dioxide.

Earth Observation (EO) systems have played key role in providing evidence-based information. The Geographic Information System (GIS) has enhanced value by integrating environmental variables, modeling, and simulation. NASA – first launched Landsat in 1972 and has kept as a continuity mission (most recent being Landsat 9). NASA/ESA/ISRO/CNSA/JAXA launches and maintains data (50m to 5m) resolution in the open domain. The commercial or strategic (<1m) are priced often very high. The images of the entire Earth every 16 days (daily through constellations) are possible. The emerging constellation for increased temporal resolution. The multiplatform options (satellite, aerial, drone) are available to collect and process the bulk data using machine learning and artificial intelligence. New opportunities are emerging with new sensor systems like LiDAR and Thermal region. The recent review of Sustainable Development Goals (SDG) carried out in 2014 concludes that EO has hastened the process. The satellite and derived products need to reach all stakeholders. The Geospatial and Space Policies of India have shown the direction but relevant organizations have to take bold steps.

The world is currently likely to hit 3?°C of warming above pre-industrial levels by 2100 (although recent policy announcements from the United States and China could reduce this). The 2015 Paris climate agreement aims to limit the global temperature rise this century to well below 2?°C, and, ideally, to 1.5?°C. There is no date for either goal, beyond the “end of this century”. The metric that matters most is the peak temperature, with more aggressive efforts required to stay below 1.5?°C of warming than for the 2?°C target.

There are various options for doing this. For example:

1. Biomass vegetation is burnt for energy, and the emitted CO2?can be retained and stored underground;
2. Involve industrial machines that capture CO2?from the air; these are currently nascent, expensive technologies;
3. Restore ecosystems, such as wetlands, so that they sequester carbon.
4. Improve land management — for timber, crops, and grazing;
5. Reduce emissions of carbon, methane, and nitrous oxide, as well as sequester carbon

The review of SDGs in 2014 reveals that only 17% of targets are on track, hindered by factors such as the pandemic, conflicts, and climate issues. The developing countries face additional challenges, with high debt and a?$4 trillion annual SDG investment gap. The space technology has made a remarkable contribution to progress towards achieving the envisaged goals. However, there is uneven access to Space Technology and it should be ensured that all humanity can continue to use outer space for peaceful purposes and socioeconomic benefit now and in the long term through global partnerships. This will require international cooperation, discussion, and agreements designed to ensure that outer space is safe, secure, and peaceful.

Innovations for Cooling Solutions are coming!

Geothermal cooling could harness the Earth’s stable underground temperatures;

Solar cooling technologies (both active and passive energy systems), will become cooling sources;

Quantum cooling, a technique rooted in quantum mechanics, is an exciting development in cooling technology, still largely in its research phase. It works by manipulating quantum states to dissipate heat, allowing for cooling efficiencies beyond the capabilities of traditional methods;

Absorption cooling technology employs a heat source, often from renewable energies like solar power or industrial waste heat, to drive a thermochemical absorption process for cooling;

Ice-powered air conditioning technology generates ice during off-peak, low-demand hours, using this ice to cool buildings during peak heat periods; and

Magnetic refrigeration, featuring an innovative cooling design, is a cutting-edge technology that utilizes the magnetocaloric effect.