The environmental changes pose new challenges to international law. As predicted in the Intergovernmental Panel on Climate Change synthesis report[12] the average temperature of the air and the sea, pollution and other symptoms of a changing climate will likely lead to a rise of the sea level, desertification, deforestation, extreme storms and  earthquakes[13].

A rising sea level is not only likely to have an impact on salt-water intrusion, coastal erosion, more destructive storms and decreased freshwater ability in various states.  It also generates the possibility of flooding a state totally.[14] For some states even a small rise of the sea level may be a challenge; for others, it may lead to the mere disappearance of the state’s territory. For instance, in Tuvalu, a tiny island country in the Pacific Ocean lying midway between Hawaii and Australia, the highest point over sea level reaches 4.5 meters. Other island states face this problem as well, such as Kiribati, Tonga and Fiji.

Other regions and countries such as Sub-Saharan Africa, the Indian sub-continent, China, Mexico and Central Africa are not or not only suffering from the potential rise of the sea level. There the desertification, drought, disruption of monsoon and other rainfall systems cause people to be put at risk of displacement. There are estimated 25 million environmental refugees today and the numbers are likely to grow even faster in future. (Myers, 1997 )

The core legal international in regard to refugees is the 1951 Convention Relating to the Status of Refugees and the 1967 Protocol to the convention, in which the refugee is defined as:

"A person who owing to a well-founded fear of being persecuted for reasons of race, religion, nationality, membership of a particular social group or political opinion, is outside the country of his nationality and is unable or, owing to such fear, is unwilling to avail himself of the protection of that country; or who, not having a nationality and being outside the country of his former habitual residence as a result of such events, is unable or, owing to such fear, is unwilling to return to it.."[15]

Within this definition there is no legal status provided for persons who are constrained to leave their home country because of environmental factors.  First, an environmental disaster, such as a flood, cannot be considered a persecution without unreasonably stretching the terms of the Convention.  Second, as long as the inhabitants of areas expected to be flooded are still living in their home country, they are still considered to be under the protection of this state, which precludes them from being legally considered refugees. 

In international law a state is defined over territory, population and power of a state. If there would no longer exist a state territory it would no longer be subject to international law. Without being subject of international law there would not exist a citizenship to this state. There would occur a further complication to international law when suddenly a great number of citizens of a no longer existing state  were searching for asylum. The 1954 Convention relating to the Status of Stateless Persons[16] is an instrument on this issue but does not focus on the possibiliy of environmental refugees.

By the end of the 20^th century the definition of “refugee” had been extended bringing international protection to people “who are forced to move for a complex range of reasons including persecution, widespread humanitarian rights abuses, armed conflict and generalized violence”[17] However this extended definition does not cover environmental refugees and forced the refugees who fled Mozambique because of a drought to claim political refugee status in Zambia.[18]

While refugees are persons displaced outside their home country, internally displaced people (IDP) are persons displaced within the borders of their country.  In 1998, the United Nations Secretary-General’s special representative for displaced persons, Francis M. Deng, proposed a definition for internally displaced people (IDP) which clearly incorporates environmentally displaced persons[19]:

''Internally displaced persons are persons or groups of persons who have been forced or obliged to flee or leave their homes or places of habitual residence, in particular as a result of or in order to avoid the effects of armed conflict, situations of generalized violence, violations of human rights or natural or human-made disasters, and who have not crossed an internationally recognized state border''[20]

However, this definition has no authoritative value, since there are no international conventions that mention displaced persons. Displaced persons do not form a category under international law[21]. 

Environmental refugees therefore don’t exist in regard to current international law. Persons who are forced to leave their country for environmental reasons are not granted any legal status. The United Nations High Commissioner for Refugees (UNHCR), the International Organization for Migration (IOM) and the Refugee Policy Group all use the term “environmentally displaced persons” rather than “environmental refugees”.  Environmentally displaced persons are defined as “persons who are displaced within their own country of habitual residence or who have crossed an international border and for whom environmental degradation, deterioration or destruction is a major cause of their displacement, although not necessarily the sole one”[22]. There is no status provided for the persons, who have to cross the border and cannot return to their country.

In its 1985 report for the United Nations Environment Program entitled Environmental Refugees, El-Hinnawi has defined environmental refugees as “those people who have been forced to leave their traditional habitat, temporarily or permanently, because of a marked environmental disruption (natural and/or triggered by people) that jeopardized their existence and/or seriously affected the quality of their life”[23].  However, it is argued by some that a more narrow definition is more appropriate, in order to differentiate environmental migrants, who make a “voluntary, rational choice of leaving their country”, from environmental refugees, who “are compelled to flee by sudden, drastic environmental change that cannot be reversed”[24].

It is possible to expand the 1951 Convention along human rights lines. The Refugee Convention clearly recognizes that refugee status results from the denial of human rights but the Convention also recognizes the right to seek safety, as contained in Article 14(1) of the Universal Declaration.[25] Both the International Covenant for Civil and Political Rights and the International Covenant for Economic and Social Rights acknowledge the "inherent right of all peoples to enjoy and utilize fully and freely their natural wealth and resources" and "in no case may a people be deprived of its own means of subsistence."[26] When people are deprived of their means of subsistence and can no longer enjoy their resources are their human rights sufficiently hurt to seek asylum in a differente state?

Critical voices often claim that an environmental refugee is often not solely seeking asylum because of an environmental issue.(Keane 2004) The environmental aspect is often closely related to economic and social reasons. There is a lack of evidence, that the environment can be the sole and substantive cause for migration although a linkage of the both terms is agreed on.

The primary questions which have to be addressed in regards to the aforementioned issue are: 

• If the Environment is sometimes linked with other reasons for leaving a state, what legal status can an environmental refugee be given?
• Has the term environmetal refugee to be included in the Convention in order to fit international human rights law? 
• How should stateless persons be legally treated when there does no longer exist an origin country where they can return to? 
• What are the measures that can be taken to prevent environmental refugees?