To prevent irreversible damage to the planet’s ecosystem, much is to be accomplished at a global scale.

Envisioning a Successful Steady-State Economy
A steady-state economy is in a stationary state, with a constant stock of population and capital which result in long-term continuance of the economy. The economy is a subsystem within Earth's non-growing capacity. Growth needs to be limited to an optimal scale to prevent environmental and social costs outweighing economic growth benefits. ‘Good growth’, 'Green growth' and optimization of the economy are ineffective due to the Jevons paradox which states that initial resource reductions or efficiencies will result in further growth. As production becomes more efficient and cost savings are experienced, businesses are able to reinvest into further growth or decrease prices leading to cheaper consumerism which resultantly heightens consumption. A steady-state economy cannot be reached where naturalism is the guiding tool for people who are guided by individual purpose and rationalism. Policies needs to correct for such behaviours to ensure long-run economic continuance.
Is green growth possible?
Green growth strives for economic growth within our earth's planetary boundaries. If economic growth is the goal, absolute decoupling from resource use and emissions is unrealistic. Only a small amount of throughput has circular potential and in the case of emissions, decoupling could not happen fast enough to meet the carbon budget of 1.5-2 degrees. Green growth advocates for increased efficiency whilst achieving growth, the rebound effect however results in efficiency gains being cancelled by increased capital for further growth and consumption. Therefore, alternative strategies are necessary, such as decoupling prosperity and development from GDP growth. Green growth could be possible if GDP growth rates drastically lower to under 1% which in today’s economy would be regarded as politically unacceptable. With the absence of science governing policies advocating green growth, there is reason to believe these assumptions are politically motivated.
Growth and degrowth in Marx’s Critique of political Economy
Transitioning to Degrowth entails overcoming the growth paradigm of Neo-liberalism which is the economy’s natural state. It’s ingrained into social structures, commodity usage, and the growth imperative; stemming from post-world war Fordism when upward mobility was to rebuild society. Organizational and technological restructuring led to the structural functionalist perspective where unequal distribution of income became accepted, bringing forward a meritocratic society which persists. The growth imperative now exists to benefit the individual, not society. Marxism shows Degrowth needs to overcome the growth paradigm and the perspective of those following it as the nature of actions between labor and nature take place in social forms often exploitive and inequitable yet regarded as natural. Capitalist economies expand through surplus value created by workers in return for a wage to buy commodities. There is a continuous chase for productivity. However simultaneously a race to the bottom environmentally.
Degrowth
Alternative ways for articulating the society, economy and nature. Completely overthrowing the current economic paradigm of growth, also calls for a drastic change in processes within the economy, moving towards a different structure, with different principles to serve different functions. Degrowth connects to the worldview of ‘living well’. Furthermore, degrowth should be a choice made by individuals who can act independently without being pressured by the system to continually consume and aim for growth.
Innovation can’t escape ecological crisis, there are limits and economic activity and cannot fully be decoupled from environmental impact. Maintaining the economy would require constant energy to maintain order, resulting in environmental cost. Decoupling economic growth from environmental impact is not possible neither is there evidence of the rebound effect of green technologies. Degrowth allows for liberation from the growth imperative.
My thought...
According to Neoclassical assumptions, people act rationally and independently on perfect information being full and relevant. This can however be contested as Neoclassical Economics has guided us from the stability of the Holocene into the Anthropocene, the first epoch where the earth and its ecosystems are being significantly impacted by human activity.
There are inherent differences between a steady-state economy, green growth driven economies and degrowth economies, although regardless of their differences, there is one shared thought being the recognition of the failing nature of neoclassical economics. Today’s society fuels competition, racing for surplus growth which results in increased capital for more investment, more growth, more money and more possessions. The costs of all this growth is shifted to the environment as resources are depleted while earths sinks overwhelmed. Non-renewable resources are being depleted, renewable resources which are supposed to be plentiful and infinite therefore often regarded a common good, are being over stressed to the point where even they are being driven to scarcity or extinction. The tragedy of the commons provides a good explanation for this, and looking at the oceans and how it is forecasted to be empty by 2048, we see that not even renewable resources can remain in balance with humans limitless intervention.
Growth cannot be achieved without further detriment to the Earth's ecosystem, due to the second law of thermodynamics, entropy increases without constant input of energy, therefor complete decoupling of growth from emissions is unrealistic, contrary to the ideology of Green Growth. There are no perfect circles, materials loose utility and there are always outflows (heat, waste, energy etc.) and constant energy is needed to prevent such dissipation. There is an unequal ecological exchange as high quality, usable matter is extracted from the environment for throughput within the economy, the output is high, entropy waste which pollutes or needs energy to reach a usable state again.
A steady state economy aims to find equilibrium, an operational economy that doesn’t cross ecological boundaries. Maintaining a constant balance to ensure the planets continuance for future generations, growth is not the measurement of a steady-state economy which stands rather stagnant. The idea is wonderful, but I see difficulty in how it is to be controlled. A steady state economy maintains a constant flow of resources and holds a constant population but if this steady state is built by maintaining the Earth's current state, we will certainly reach climate catastrophe.
In current meritocratic society, the growth imperative of Neoclassical economics feels natural and has resulted in short term capital gains thinking rather than long term continuance through conservation of the planets finite and infinite resources. Decoupling growth from emissions, the Jevons paradox shows us that efficiency in supply chains, such as better use of resources, reduced material and clean energy sources will only reduce cost and fuel further consumption. In other words, using policy may be the only way to put a ceiling on consumerism to account for the market failures of such negative externalities, this could be done through Pigouvian tax or cap-&-trade.
I believe Degrowth is the only way to reverse the worst effects of environmental degradation. Simply described, Degrowth is a voluntary transition to a just, participatory, and ecologically sustainable society, meeting all’s basic needs and ensuring high quality of life. And if green growth is the goal, Degrowth must first bring the economy into an optimum state. Similarly, taking the steady state approach, a period of Degrowth is necessary as the current economy is overstressing the earth's capacity and threatening its continuance.