The International Organization for Migration (IOM) defines environmental migrants as "persons or groups of persons who, mainly for reasons related to sudden or gradual environmental change adversely affecting their lives or living conditions, are forced to leave their homes or leave them on their own initiative, temporarily or permanently, and thereby move within or out of their country. " Environmental migration can take many complex forms: forced and voluntary, temporary and permanent, internal and international. People who migrate for environmental reasons do not clearly fall into any particular category under the existing international legal framework. Terms such as "environmental refugee" or "climate refugee" have no legal basis in international refugee law. There is a growing consensus among relevant agencies, including UNHCR, to avoid their use.
Although the Syrian migration wave is mainly related to the Syrian civil war, it has been exacerbated by environmental issues such as drought. The article below highlights how the Syrian case proves how the effects of environmental degradation and global warming affect countries' political stability, with consequences on a global level.
https://www.lifegate.com/syria-the-environmental-crisis-behind-the-civil-war
Political migration is any migration motivated primarily by political interests. Typically, political migration is in one of two classes, private or government, depending on who encourages the migration. Political migrations differ from other migrations by attempting to change aspects of a political system. These changes are accomplished by modifying the demographics of a specific region. The focus on demographics necessitates an emphasis on migration towards low-population regions or artificially creating high-population regions. - https://www.definitions.net/
Political migration can be caused by different societal phenomena, below you can see a non-exhaustive list of political practices leading to mass migration.
State persecution involves the harassment, discrimination, and torture of people who disagree with their government, have minority religious beliefs or ethnic backgrounds. Governments can also force cultural groups to move from one place to another (within or outside the country) to gain political advantage in having less cultural diversity. Because conditions in their country are unsafe, these people are forced to migrate to safer countries. Asylum seeking is a direct result of the outflow of political migrants from an oppressive state to a more democratic country.
the rise in claims of persecutions in countries such as ****Iraq, Zimbabwe, Somalia, Afghanistan, or China.
The lack of political liberties and rights, and endemic corruption act as push factors for migrants seeking greater freedoms. Even though they are not persecuted in their places of birth, concerns that limit people’s freedoms cause them to leave. If the political environment is hostile, then the economic situation is likely to be poor. This triggers migration for political and economic reasons. Most migrants leave for more democratic countries where they can pursue better careers, education, and freedom.