Challenges, barriers and solutions in achieving net zero

Net zero (NZ) refers to the equilibrium between the amount of greenhouse gases introduced into the atmosphere and the amount removed from it. The Paris Agreement set a goal of limiting global warming to 1.5 °C above preindustrial levels, which requires global net zero CO₂ emissions to be reduced by approximately 2050. This chapter describes various techniques to reach NZ emissions, including carbon accounting, modeling, policy analysis and evaluation, and stakeholder engagement. Impurities can be removed from solid, liquid, or gas substrates by using natural resources like biochar (a natural adsorbent). Biochar can reduce greenhouse gas emissions of CH4 by 39.5% and N2O by 30.92%. One essential element in advancing agriculture toward Agriculture 4.0 is the integration of sensors for measuring soil quality. Electricity consumption increases from 23 to 33 EJ to compensate for energy recovery, whereas biomass consumption decreases from 101 to 62 EJ. This work is novel because it thoroughly examines the behavioral and psychological obstacles to NZ, the relationship between indigenous knowledge and NZ pathways, the use of AI and digital twins to overcome these obstacles, the accessibility of green finance for SMEs in the NZ transition, the role of the circular economy as a NZ accelerator, geopolitical constraints and global equity in NZ commitments, and hyperlocal NZ initiatives in urban informal settlements. Decarbonised industry, zero-emission transport, smart NZ cities, nature-based solutions, technology and artificial intelligence for climate change, carbon markets, and financial innovation are among the future perspectives for achieving NZ.