Ethiopia is a predominantly rural society. The country experiences a very variable pattern of rainfall. Crop failures and livestock losses can occur when seasonal rains fail, or when excessive rain causes flooding.
Pastoral nomads have increasing difficulty in finding water or suitable grazing for their animals. In extreme cases, as in 1984-1985, this results in famine and massive migration movements occur.
The famine of 1984-1985 resulted in the death or displacement of hundreds of thousands of people within Ethiopia. Around 300,000 people fled to Sudan and approximately 100,000 people fled to Somalia.
Forced migrants do not always cross international boundaries. In the drought conditions of 1999-2000, Christian Aid reported migration within Ethiopia - into towns, to search for work or beg for food and into areas of the country where the rainfall was more reliable.
These movements can cause conflict between fellow Ethiopians competing for scarce resources or work opportunities.
Ethiopia is also host to refugees fleeing the current crisis in South Sudan. The United Nations Refugee Agency (UNHCR) estimates that over 500,000 million people have recently fled from their homes.
The Syrian crisis is an on-going armed conflict in Syria between forces loyal to the Ba'ath government and those opposing them.
In 2016, reports estimated that fatalities caused by the civil war in Syria amounted to 470,000.
An estimated 4.5 million refugees have fled the country, many to neighbouring countries such as Lebanon and Jordan. The infographic below shows the figures in 2016.
In addition, over six million people are estimated to be internally dispalced within Syria trying to escape escalating violence.
A large share of Syrian refugees in Jordan are not in camps and have fled into urban areas, beyond the reach of direct assistance from the UN and other donors.
Roughly 70 per cent of these refugees are estimated to be hosted in local communities, resulting in enormous strain on public resources.
This leads to tensions with the native community as resources are strained.