Climate change is a very real catastrophe that has been on everyone's radar for years now.
Rising greenhouse gases = rising temperatures = very bad news for the planet.
But the United Nations' panel of experts' latest landmark report on the issue might be the scariest yet.
Even temperatures 1 or 2 degrees Celsius higher than pre-industrial levels would carry "considerable" risks for Earth, according to the Intergovernmental Panel on Climate Change's report.
A temperature hike of 4 degrees Celsius or higher would be "catastrophic."
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GlobalPost outlines the eight major risks we face if climate change goes unchecked:
(Manan Vatsyayana/AFP/Getty Images)
This reality isn't in some nebulous future: As Senior Correspondent Corinne Purtill reported in February, much of the United Kingdom spent the first few months of 2014 practically underwater with constant rains and floods.
And floods caused by a deadly monsoon in India last year claimed at least 1,000 lives, and stranded tens of thousands.
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The availability of ground and surface water would go down "significantly," especially in arid countries already suffering from years of drought. Climate change would only intensify competition for the finite resource, according to the report.
The northeastern part of Brazil has been suffering from a two-year-long drought, with little hope of respite. It's a silent disaster, probably the biggest you haven't heard of.
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The risk of coastal flooding and land loss due to rising seas would skyrocket in the coming decades, partly due to rising populations and further urbanization of coastal areas.
Small islands and some low-lying countries would be particularly water-logged.
Mexico's tourist hotspot Cancun is already losing its famous sandy beaches thanks to erosion. Scientists remain wary of connecting specific weather events to climate change, but the Caribbean's warming seas have made devastating hurricanes — like the one that swept away eight miles of Cancun's beach in 2005 — more likely.
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Death and illness from heat waves and poor nutrition would rise, as would the spread of mosquito- and water-borne diseases, according to the report.
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All food production may be hit by climate change in the coming years if left unchecked, according to the report, but especially cereals and fish stocks.
Wheat, rice and maize production would likely decline by mid-century. The risk would then become more severe beyond 2050, especially in tropical and sub-tropical regions. The hauls of fishermen are projected to fall by 40 to 60 percent, according to the report.
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(Piotr Naskrecki/Conservation International Courtesy)
A "large fraction" of land and freshwater species would be at risk of extinction because their habitats would be destroyed, according to the report.
A 2-degree risk in global temperatures would put coral reefs and arctic species at very high risk.
In Belize, the coral reefs had adapted to withstand storm waves, but thanks to stronger cyclones, dead coral nearly carpets the seafloor, stripped of its color and smashed to pieces.
And deep in the Madagascan rainforest, the last two greater bamboo lemurs face peril as their main food source — bamboo — is affected by changing patterns of rainfall.
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It may not seem obvious, but climate change can "indirectly increase risks of violent conflicts in the form of civil war and inter-group violence," according to the report.
Tensions would simmer with the rise of poverty, hunger and homelessness, the report authors concluded. Conflicts may also arise over fishing boundaries and water supplies as rising seas gobble up land and flood over borders.
Already, Africa's Sahel region has seen a rise in conflict as land and resources shrink. Marshall Burke of the University of California told GlobalPost, "Years of bad climate — in particular, years of unusually hot temperatures or extreme rainfall — substantially increases the likelihood that many different types of conflict might occur."
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The rise of extreme weather events like hurricanes and typhoons could cause a breakdown of infrastructure networks and critical services like electricity, water supply and health and emergency services, according to the report.
Farmers in developing nations would be especially at risk of losing their livelihoods and falling into poverty.
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