A desert is an extremely dry area of land with extreme environments and sparse vegetation. They are likely to develop in areas where annual precipitation is less than 250 mm. It is one of Earth’s major types of ecosystems, supporting a community of distinctive flora and fauna specially adapted to the harsh environment. Geologists group deserts into five categories:

• Subtropical deserts: They are found along the Tropic of Cancer, between 15 and 30 degrees north of the Equator, or along the Tropic of Capricorn, between 15 and 30 degrees south of the Equator, where convection cells diverge. They are caused by the circulation patterns of air masses. Hot, moist air rises into the atmosphere near the Equator. As the air rises, it cools and drops its moisture as heavy tropical rains. The resulting cooler, drier air mass moves away from the Equator. As it approaches the tropics, the air descends and warms up again. The descending air hinders the formation of clouds, so very little rain falls on the land below. Subtropical deserts include the Sahara Desert in Northern Africa, the Kalahari Desert in Southern Africa, and the Tanami Desert in Northern Australia.
• Coastal Deserts: Cold Ocean currents contribute to the formation of coastal deserts. They are generally found on the western edges of continents near the Tropics of Cancer and Capricorn. Winter fog, produced by upwelling cold currents, frequently blankets coastal deserts and blocks solar radiation. The heavy fog drifts onto land. Although humidity is high, the atmospheric changes that normally cause rainfall are not present. For example, the cold Humboldt Current flowing from Antarctica to Southern Chile creates the Atacama Desert of South America, while the cold Benguela Current is critical to the formation of the Namib Desert.
• Rain Shadow Deserts: These deserts exist near the leeward slopes of some mountain ranges. When moisture-laden air hits a mountain range, it is forced to rise. The air then cools and forms clouds that drop moisture on the windward (wind-facing) slopes. When the air moves over the mountaintop and begins to descend the leeward slopes, there is little moisture left. The descending air warms up, making it difficult for clouds to form. For example, the Death Valley, in the U.S. is in the rain shadow of the Sierra Nevada mountains. Similarly, the Patagonian Desert lies in the rain shadow position on the leeward side of the Andes.
• Interior Deserts: They are found in the heart of continents. By the time air masses from coastal areas reach the interior, they lose all their moisture. They are sometimes called inland deserts. For example, the Gobi Desert in China and Mongolia.
• Polar Deserts: Parts of the Arctic and the Antarctic are classified as deserts. They are very dry, but not in the traditional sense. Unlike other types of deserts, they are cold all year round with frigid winters. Instead of sand, the surrounding surface is covered in layers of ice and snow. They experience little precipitation because, above 66°N and S latitude, there is very little moisture in the air due to extreme cold temperatures.

Deserts are found on every continent and cover about one-fifth of Earth’s land area. They are home to around 1 billion people-one-sixth of the Earth’s population. It has been observed that in semi-arid areas that border deserts, climate change and human activities have led to increased desertification.

Ocean Thermal Energy is harnessed through a process called Ocean Thermal Energy Conversion (OTEC). OTEC is a process or technology for producing energy by harnessing the temperature differences (thermal gradients) between ocean surface waters and deep ocean waters. The OTEC system uses a temperature difference of at least 20 degrees Celsius to power a turbine to produce electricity. India has a theoretical potential of 180,000 MW of ocean thermal energy. India is geographically well-placed to generate ocean thermal energy, with around 2000 kms of coastal length along the South Indian coast, where a temperature difference of above 20 degree Celsius is available throughout the year.
To tap ocean thermal energy, the National Institute of Ocean Technology, under the Union Ministry of Earth Sciences (MoES) is establishing an Ocean Thermal Energy Conversion Plant with a capacity of 65 kilowatts (kW) in Kavaratti, Lakshadweep. The plant will power the one lakh litres per day low temperature thermal desalination plant, which converts seawater into potable water. The plant is the first of its kind in the world as it will generate drinking water from sea water using indigenous technology, green energy and environmentally friendly processes.
However, progress in this regard has been slow due to various challenges:

• High cost: Setting up of OTEC plants for harnessing thermal energy potential requires significant costs of pumping and piping infrastructure. It is economical at very large scales only. The small land based OTEC plants need kilometres of piping to move a high volume of cold water from deep ocean. Its cost could be up to 75% of the total power plant costs.
• Restricted location: The suitable locations to harness OTEC are reduced to equatorial and tropical zones.
• Lack of technology: Most technologies are currently at pre-R&D demonstration stage of the initial stage of commercialization.
• Environmental concerns: It can have potential impact on marine organisms and ecosystems due to discharge of cooler, denser and nutrient rich water from the plants, entanglement in cables, entrapment, noise generation and pollutants. It can also lead to biofouling i.e. unwanted accumulation of algae, microorganisms, plants etc.

Remedial measures required in this context:

• Policy support is required for harnessing the potential of ocean thermal energy. It should not only include a robust national policy, but a proper plan of financial deployment to accelerate the existing program.
• There is a requirement of investment in R&D. Private sectors should be encouraged and be given incentives to contribute to technological development in this regard.
• India should take efforts to promote international collaborations in the field of utilising ocean energy and also bring littoral countries on a single platform for contributing in this field.
• There is a need to develop more demonstration projects at feasible sites so that a careful study of EIA can be done.

Ocean thermal energy has the potential to generate a constant, clean source of electricity unlike intermittent electricity from renewable resources like wind and solar. So, there is a need to create awareness about the potential of ocean thermal energy and its long-term benefits including reduction in carbon dioxide emissions.

The National Logistics Policy (NLP) formulated by the Ministry of Commerce and Industry was launched in September 2022. It aims to lower the cost of logistics from the existing 13-14% and lead it to par with other developed countries. The Policy lays down an overarching interdisciplinary, cross- sectoral, multi-jurisdictional and comprehensive policy framework for the logistics sector. The policy complements the PM GatiShakti National Master Plan. Following major steps would be taken under NLP that have the potential to transform India’s logistics ecosystem:

• Integration of Digital System (IDS): There will be digital integration of different systems of seven various departments (like road transport, railways, aviation, commerce ministries and foreign trade). The digital data of these ministries is to be integrated under the IDS. This will help smoothen cargo movement and reduce logistical costs,
• Unified Logistics Interface Platform (ULIP): This will ensure shorter and smoother cargo movement and enable the exchange of information confidentially on a real-time basis.
• Ease of Logistics: E-Logs, a new digital platform, will allow industry to directly take up operational issues with government agencies for speedy resolution. It will enable and ensure the ease of logistics business through transparency and accessibility.
• System Improvement Group: It will monitor all logistics-related projects regularly through a group of officers from ministries concerned.

The above-mentioned processes will not only help in streamlining the regulatory environment in the country but also boost employment creation:

• Growth of the sector: According to the Ministry of Commerce and Industry, the Indian logistics sector provides livelihood to more than 22 million people and improving the sector will facilitate a 10% decrease in indirect logistics cost leading to the growth of 5 to 8% in exports.
  • The NLP policy would accelerate hiring and creating new job roles in transport, supply chain management, digital warehousing and other fields and would also help the economy to recover from challenges faced during pandemic.
• Multiplier effect: The policy would significantly impact the manufacturing and infrastructure sectors, potentially making India the next global manufacturing hub. Infrastructure development has a multiplier effect on the economy, fuelling faster job creation in the cement, steel, and machinery subsectors of the construction industry.
• Human Resources Development: Most entry-level workers in India are hired by the infrastructure and construction industries. Providing them access to a skilling ecosystem can further boost their productivity, earnings potential, return on investment (ROI), and project turnaround time.

NLP is a significant step as it endeavours to make India to be among the top 25 countries by 2030 in the Logistics Performance Index ranking, and create data driven decision support mechanism for an efficient logistics ecosystem. However, for its effective implementation and desired outcome all stakeholders including the states should be aligned to the stated objectives of the policy.