No one, as yet, has come up with a solution to the great challenge facing those who want to settle Mars - terra forming. Mars can't be settled until it has an ecology - an atmosphere, weather, precipitation, all the things that sustain life on Earth. Some estimates claim that would take millennia, possibly hundreds of thousands of years. We haven't got that kind of time.
Before we tackle establishing a suitable environment on Mars, we should direct our efforts at restoring our endangered ecosystems right here on Earth.
Around the world our existing ecosystem that has nurtured mankind for tens of thousands of years is on the verge of collapse. You might have thought that the most powerful among us, those we elect to high office and entrust with the reins of power, would have rallied to respond. If you believe that, you are wrong.
A call to arms was sounded in January. It took the form of a paper published in the journal, Frontiers in Conservation Science, "Underestimating the Challenges of Avoiding a Ghastly Future." The warning is blunt.
"Future environmental conditions will be far more dangerous than currently believed. The scale of the threats to the biosphere and all its lifeforms—including humanity—is in fact so great that it is difficult to grasp for even well-informed experts."
Even the experts are struggling to grasp the enormity and immediacy of the threat. Yes, this is a present danger, not something that your grandkids will have to deal with.
The authors, "ask what political or economic system, or leadership, is prepared to handle the predicted disasters, or even capable of such action."
The verdict is plain - our leaders don't get it. Whether that's from ignorance, neglect or willful blindness really doesn't matter.
"We especially draw attention to the lack of appreciation of the enormous challenges to creating a sustainable future. The added stresses to human health, wealth, and well-being will perversely diminish our political capacity to mitigate the erosion of ecosystem services on which society depends. The science underlying these issues is strong, but awareness is weak. Without fully appreciating and broadcasting the scale of the problems and the enormity of the solutions required, society will fail to achieve even modest sustainability goals."
On the loss of biodiversity, the report notes that the loss rate is well within extinction-level values.The IUCN estimates that some 20% of all species are in danger of extinction over the next few decades, which greatly exceeds the background rate. That we are already on the path of a sixth major extinction is now scientifically undeniable (Barnosky et al., 2011; Ceballos et al., 2015, 2017).
Large population size and continued growth are implicated in many societal problems. The impact of population growth, combined with an imperfect distribution of resources, leads to massive food insecurity. By some estimates, 700–800 million people are starving and 1–2 billion are micronutrient-malnourished and unable to function fully, with prospects of many more food problems in the near future (Ehrlich and Harte, 2015a,b). Large populations and their continued growth are also drivers of soil degradation and biodiversity loss (Pimm et al., 2014). More people means that more synthetic compounds and dangerous throw-away plastics (Vethaak and Leslie, 2016) are manufactured, many of which add to the growing toxification of the Earth (Cribb, 2014). It also increases chances of pandemics (Daily and Ehrlich, 1996b) that fuel ever-more desperate hunts for scarce resources (Klare, 2012). Population growth is also a factor in many social ills, from crowding and joblessness, to deteriorating infrastructure and bad governance (Harte, 2007). There is mounting evidence that when populations are large and growing fast, they can be the sparks for both internal and international conflicts that lead to war (Klare, 2001; Toon et al., 2007). The multiple, interacting causes of civil war in particular are varied, including poverty, inequality, weak institutions, political grievance, ethnic divisions, and environmental stressors such as drought, deforestation, and land degradation (Homer-Dixon, 1991, 1999; Collier and Hoeer, 1998; Hauge and llingsen, 1998; Fearon and Laitin, 2003; Brückner, 2010; Acemoglu et al., 2017). Population growth itself can even increase the probability of military involvement in conflicts (Tir and Diehl, 1998). Countries with higher population growth rates experienced more social conflict since the Second World War (Acemoglu et al., 2017). In that study, an approximate doubling of a country's population caused about four additional years of full-blown civil war or low-intensity conflict in the 1980s relative to the 1940–1950s, even after controlling for a country's income-level, independence, and age structure.
The dangerous effects of climate change are much more evident to people than those of biodiversity loss (Legagneux et al., 2018), but society is still finding it difficult to deal with them effectively. Civilization has already exceeded a global warming of ~ 1.0°C above pre-industrial conditions, and is on track to cause at least a 1.5°C warming between 2030 and 2052 (IPCC, 2018). In fact, today's greenhouse-gas concentration is >500 ppm CO2-e (Butler and Montzka, 2020), while according to the IPCC, 450 ppm CO2-e would give Earth a mere 66% chance of not exceeding a 2°C warming (IPCC, 2014). Greenhouse-gas concentration will continue to increase (via positive feedbacks such as melting permafrost and the release of stored methane) (Burke et al., 2018), resulting in further delay of temperature-reducing responses even if humanity stops using fossil fuels entirely well before 2030 (Steffen et al., 2018).
The gravity of the situation requires fundamental changes to global capitalism, education, and equality, which include inter alia the abolition of perpetual economic growth, properly pricing externalities, a rapid exit from fossil-fuel use, strict regulation of markets and property acquisition, reigning in corporate lobbying, and the empowerment of women. These choices will necessarily entail difficult conversations about population growth and the necessity of dwindling but more equitable standards of living.