How Many People Can Live on Planet Earth?

A Quarter

.. ......... of women in sub-Saharan Africa have no access to contraception.

Energy Demand

........... ............ predicted to increase over 40% in next 20 years.

Threat of Extinction

1/3 of amphibians, 1/5 of mammals under the threat of extinction.

UN Projections for Future

2.5 billion more by 2050, not even people having huge families just teens becoming parents then grandparents. India will become biggest population in world. Afghan/Sub-Saharan populations will double. Everyone in next 50 years will be affected by demographic change.

Mexico City Water Supply

8th richest on Earth - gets lots of rain however it sruggles to get actor to its 20 million inhabitants. Back up reservoirs running dangerously dry. Have had to adapt lifestyles to factor in this poor water supply - half a bucket to wash. "Everyone needs to take water issues more seriously" - David Attenborough.

Limits of Water

Already reaching limits of our environment - only 2.5% of Earth is freshwater, only 1% is available for human use. No more water on the planet than 100,000s of years ago but there are so many more of us. In 20 years almost half the population will live in areas of water stress.

Lack of Arable Land

Assess agriculture production from satellites and shows we are already using almost all of the arable land on Earth - how we gonna make double amount of food with growing population? Molly Brown says we need to raise productivity by twofold because can't use more land - need to find new, more efficient farming techniques (meat in petri dishes, GM crops).

Overusing Water

Colossal use of water in industry and agriculture - water is used so much, 3,000 litres to grow cotton for one shirt. Arol sea - fresh water lake - in last 40 years has lost 90% of water, streams leading to it used for growing cotton. Lots of countries turning to desalinisation of sea water - but lots of problems with this. Any water shortages affect agriculture then affects food supply.

Growing Food Abroad

Countries in global competition to buy land abroad to grow their food and export it back home. In lots of cases these are shady deals and shrouded in secrecy - not good for the people whose farm it is. China buying land in Africa to grow. Ethiopia is producing food for export markets whilst relying solely on international food aid to survive. Sub-Saharan Africa gonna be hit the worst - Rwanda in desperate need of food security - 80£ of Rwandans subsist on what they can grow.

Carrying Capacity

Defines amount any given capacity can support.

Demand Over Supply

Demand will eventually outstrip supply - Malthus - the Earth has physical limits and will determine how many humans it can support.

Dependence on Fossil Fuels

Dependence on fossil fuels (100 million year old animals/vegetation turned to energy) especially oil. We use 85 million barrels of oil per day - has allowed us to produce enough food and as we realise how dependent we are on oil we are starting to run out.

Resource Overshoot

Evidence that we are already in ............ ............ Research suggests we need 1.5 earths to successfully sustain us. Says people in industrial countries need to compromise energy use.

Norman Borlaug

He developed high yield crops and taught Indian/Mexican/Pakistani farmers to farm better, increased productivity fivefold and allowed countries to be self sufficient just a few years into his new ways (1965-70). Thanks to him most of the world is fed. Won Nobel Peace Prize for feeding the world - need more people like him but in the modern day, need a breakthrough.

Texan Oil

Houston, Texas, very rich due to oil reserve. But is now getting harder t find and are now trying to drill offshore - in Alaska. If these plans are successful could make 100s of billions of dollars.

Population Increase

Human pop increasing 2 ppl a second, 80 million a year, all need food, water, shelter. Human population density massive problem in almost all environmental issues. Population growth - more human suffering, also more environmental suffering.

India's Attempt to Slow Population Growth

India tried to slow pop growth - cash for vasectomies - but a lot of the people accepting cash already had like 5 kids so its pointless. The gov then used sterilisation as a punishment - in 1 year 8 million sterilised. Outrage brought down the government. Southwest India - area is stable because they all have small families - 30-40% have 1 child, rarely like 5 kids (Kerola is the SW area) - good pop as a result of good, compulsory education as well educated women tend to have smaller families. Kerola women marrying at 28 on avg, 18 in other places. Kerola shows you don't meed oppressive rule to control birth rate. Just need education and contraception.

Rwandan Civil War

Left 1 million dead in just 3 months/ Lots of fighting over resources. Teens encouraged to kill neighbours in hope of getting livestock or land.

Mexico City Vulnerable Forests

Mexico City have employed a visionary guy that wants to protect the vulnerable forest - building walls to prevent soil erosion. Use special rocks that allow water to flow through to the city to use it. Need to catch it in forest - if they lose the forest, they lose the water supply. Works with local forest owners who make sure no pollution and damage happens to the forest.

1 Billion

Over ............. lack access to clean drinking water- gonna get worse and worse, will impact rich, not just poor.

Global Hectares

Productive bio capacity of earth (.......... ..........). Africa uses half their share of hectares. Average American uses over 5 times their share - all about equality! If all humans used the hectares the Rwandans used we could sustain 18 billion and 1.5 billion of those living in the USA.

3 Ways to Solve Population Problem

Reduce population growth. Consume less energy. Make new sustainable technology.

Contraception in Rwanda

Rwanda have made countrywide contraception a great government priority. They are helped to understand whilst having lots of kids is good, having too many can put some of their kids at risk.

Better Healthcare

The reason for such huge rise in population is improvement in controlling illnesses - life has got better in the 50 years but there are serious consequences.

Problems With Reducing Population Growth

When governments try reduce children allowed - always controversy - can only work in severely oppressed countries, like China. Wouldn't happen in Britain or France etc.

400 Million

Without 1 child policy there would be an extra ... .......... more people in China.