First of all I want to say that I know lots of global problems but I decided to write only about one of them: HUMAN POPULATION. Because I am keen on geography, I have some information about this topic.
Population and Feeding the World
In fact, the food scarcity part of the argument in the population debate is an interesting one -- people are hungry not because the population is growing so fast that food is becoming scarce, but because people cannot afford it. Food may be scarce, but it is international trade, economic policies and the control of land that have lead to immense poverty and hunger and therefore less access to food, not food scarcity due to over population.
Other Issues Affect and Get Affected by Population
Poverty is the number one health problem, in developing and developed nations alike. Structural Adjustment policies, for example, from the IMF have not helped in many situations as social expenditure has had to be cut back. This has led to less investment in health, education and other basic services (things that have led to a better quality of life in Europe after the second world war). Coupled with corrupt rulers and dictators, often backed by the powerful nations, due to national geopolitical interests, a large number of people have suffered.
Gender and Population Issues
By ensuring women's rights can be upheld, and realizing that women play a crucial role in the development of society, many underlying issues which lead to conflict and problems can be tackled more effectively. Better care, education and rights for women mean that children should also benefit. This can eventually allow a society to enjoy more rights and the society can be enriched.
Effects of Over-Consumption and Increasing Populations
Environmental degradation can contribute to social and political instability, which can lead to security issues. This has not currently been addressed by the foreign policy of many nations. Already around the world we are seeing an increase in violence and human rights abuses as disputes about territories, food and water are spilling into wars and internal conflicts.