timespiral
There won't be a completion date when Earth is fixed.
Mars would be too expensive because life support for humans doesn't naturally occur.
We have to spend a lot of money just to allow us to take a breath on Mars. However, Mars has lower gravity. I could imagine this might be an advantage for construction or any activity that requires lifting. Mining operations might be cheaper. Eventually, Mars "could" be made more habitable, but that is far off in the future.
Quadrillian
Unfortunately we have passed the point of no return on this planet, and the collapse of civilisation is now baked in. However that opens up opportunities, as it is only industrial civilisation that is doomed, not necessarily Homo sapiens ourselves. In the post industrial world, survivors will live a feudal existence much as humans have done over all of history. All that will happen is the anomaly of the last century will be corrected.
Obviously if this is going to happen, there is no additional burden on the global budget, straining as it is under $230trillion dollars in debt. The best we can do is to regulate the severity and suddenness of the collapse to maximize options for survivors. No extra costs involved.
Colonizing Mars would involve an enormously expensive global industry that would hasten and intensify the collapse of civilisation on Earth and indeed the strain might be enough to ensure that survivors are so few that extinction becomes almost inevitable. And of course whatever hokey colony was created on Mars would collapse totally without support from Earth.
Cheers!
Brigalow Bloke
No. It is believed that the population of the Earth will begin to decline after about 30 years as women in less developed countries begin to limit their fertility. This is direct result of female education and is not imposed by government.
There are a number of likely scenarios, oil shortages will force prices up, which will limit mass use of aircraft, cars and trucks over long or even short distances. This might cause a return to, for instance, vastly more energy - efficient railways and also limit urban sprawl.
Another scenario, recently promoted by Mr Elon Musk but a reality in many places for 20 or more years is the widespread use of rooftop solar cells and high grade batteries making houses more or less independent of grid power. Even without batteries, a dozen ordinary solar cells on a roof and an inverter can cut grid power consumption by 60% or more.
Wind power and solar cells are spreading across the world. There is utterly nothing new about this.
In 1969 about one in three houses in the remote small town of Cloncurry in Australia had a solar hot water system. There was no TV and radio was terrible, but there were many solar hot water systems. In Australia, the Solarhart company alone has installed over a million solar systems since 1956.
All this will limit CO2 production eventually and a concerted effort at revegetation of land and a clean-up of oceans will make a difference too.
http://www.abc.net.au/news/2015-09-29/australia-leads-world-in-installation-of-household-solar-panels/6813532
?
Don't be absurd--the worst conditions Earth will ever face will still be far better than those faced on Mars. There are good reasons for establishing an off-world colony, but that's not one of them. I hope you aren't one of those silly people who think Mars will somehow magically solve our overpopulation problems.
.
.
Anonymous
It is not too far gone
It would be easier to live on the south pole than Mars