The latest report from the United Nations Intergovernmental Panel on Climate Change, released on Sunday night, is both sweeping in scope and staggering for its unprecedented details on the impacts of global climate change to date, as well as potential future effects on human and natural systems. The report depicts a planet already adjusting to increasingly apparent manifestations of climate change, from melting polar ice caps and rising seas to more severe and frequent heat waves.

While the report summary runs a mere 44 pages, the full chapters are far more dense and data-rich, and they amount to a summation of almost everything that scientists have learned about the impacts of manmade changes of the climate system and how such changes may alter human society and the natural world.

In an effort to tease out some of the more important findings, Mashable scoured the technical summary as well as other chapters and highlighted seven of the most important findings.

1. Climate change is not a farmer's best friend

Climate change is already dragging down crop yields, a trend that is likely to continue at the same time that population growth ensures that food demand will be rising, the report found.

The report is extremely specific when it comes to future crop yields, stating that, regardless of adaptation efforts, climate change will reduce median crop yields by up to 2% per decade through 2100, when compared to a world without climate change.

At the same time as crop yields will be challenged, crop demand will be rising by about 14% per decade until 2050, the IPCC said. “Risks are greatest for tropical countries, given projected impacts that exceed adaptive capacity and higher poverty rates compared with temperate regions,” the report found.

So far at least, climate change is having a small impact on rice and soybean yields around the world, but it has been depressing wheat and maize yields. Extreme heat events can significantly reduce crop yields, particularly when temperatures soar to or above 86 degrees Fahrenheit during the growing season.

With an increase in global average surface temperatures comes higher odds of heat waves. Extreme heat events in Russia in 2010 and the Midwest U.S. in 2012 proved that such events can lead to sharp and rapid food price swings.

The IPCC said there are measures that can be taken to help crops adapt to climate change, which would improve crop yields by about 15% to 18% of current yields, but adaptation capabilities vary from region to region and would lose effectiveness if warming is at the higher-end of projections.

2. We no longer have a choice between reducing the severity of climate change and adapting to its impacts. Climate change is here, and we have to do both.

Because of the long atmospheric lifetime of some of the main greenhouse gases, such as carbon dioxide, there is a mismatch between the payoff from climate change mitigation, which involves reducing emissions of planet warming greenhouse gases to lessen to severity of climate change, and climate change adaptation, which refers to measures to better withstand the impacts of climate change.

It used to be that these two categories were discussed separately (if adaptation was even brought up at all). But that has changed as the impacts of climate change have emerged in plain sight over the past several years.

“We’re not in an era where climate change is some sort of future hypothetical,” said IPCC working group co-chairman Chris Field of the Carnegie Institution in California, during a Sunday evening press conference. “There is no question that we live in a world that’s already altered by climate change.”

Cutting emissions now can dramatically curtail the ultimate impacts of climate change starting in the middle of this century, but until then, we’re going to have to deal with the effects of climate change already baked into the climate system.

3. It's unfair, but poor and other vulnerable populations will suffer the most from climate change.

A common thread throughout the report is that poor nations, particularly developing countries in and near the tropics, as well as poor and vulnerable populations within wealthy nations, are likely to suffer the most severe climate change-related consequences. Not only that, but global warming will introduce new roadblocks to escaping poverty. According to the report:

Throughout the 21st century, climate change impacts will slow down economic growth and poverty reduction, further erode food security, and trigger new poverty traps, the latter particularly in urban areas and emerging hotspots of hunger.

The fact that climate change is likely to deal its harshest blows to less developed nations is one of the cruel ironies about this issue — considering that it was largely the rich, industrialized world that emitted the greenhouse gases that caused the problem in the first place.

4. Higher-end warming scenarios show far greater risks of triggering “tipping points.”

The report repeatedly warns that risks associated with a global average surface temperature rise of 7.2 degrees Fahrenheit or higher would take the planet in a far riskier direction than if warming were to be contained below that level. “Large magnitudes of warming increase the likelihood of severe, pervasive and challenging impacts,” the report said.

Image: U.N. IPCC Working Group II

An unsettling fact about climate science is that researchers know that in the past, the Greenland ice sheet, and parts of Antarctica too, have melted rapidly after the climate reached a certain point. However, scientists don’t know exactly what that tipping point is (they just know it would be a bad idea to reach it).

The precise levels of climate change sufficient to trigger tipping points (critical thresholds) remain uncertain, but the likelihood of crossing tipping points in the earth system or interlinked human and natural systems decreases with reduced greenhouse gas emissions (medium confidence).

Sustained warming greater than some threshold would lead to the near-complete loss of the Greenland ice sheet over a millennium or more, causing a global mean sea-level rise of up to 7 meters [23 feet] (high confidence).

Current estimates place this threshold somewhere between 3.6 and 7.2 degrees Fahrenheit of warming compared to preindustrial levels.

5. Global warming will be harmful to the economy.

The report found that if global warming reaches 4.5 degrees Fahrenheit of warming above pre-industrial levels, it could lead to “global aggregate economic losses” of between 0.2% and 2.0% of GDP. This estimate is conservative, though, as economic impact estimates are “incomplete and depend on a large number of assumptions, many of which are disputable,” the report said. However, there is little to no evidence showing that global warming won’t be costly, rather, the challenge lies in figuring out just how expensive it might be.

6. Global warming is likely to lead to increased water stress

One of the most well-known effects of global warming is an intensification of the water cycle, with higher air temperatures leading to increased evaporation from the seas and soils, and more atmospheric water vapor contributing to more frequent heavy precipitation events. Paradoxically, climate change is projected to bring both more heavy rainstorms and more droughts, as dry regions get drier and wet areas get wetter, overall.

But the new report sheds light on the broad consequences of global warming on renewable freshwater resources, finding that each degree of warming will decrease renewable water resources by at least 20% for an additional 7% of the global population.

In other words, the warmer it gets, the more people who will be thirsty.

7. Sea-level rise and storms will combine to flood coastal cities and force millions from their homes.

One of the most dire findings in the entire report concerns the impacts of sea level rise and coastal flooding in rapidly growing areas of coastal Asia. According to the IPCC, “hundreds of millions of people” will be affected by coastal flooding and displaced by loss of their land, most of then in East, Southeast and South Asia. “Some low-lying developing countries and small island states are expected to face very high impacts and associated annual damage and adaptation costs of several percentage points of GDP,” the report said.

Sea level rise has already amplified storm surge-related coastal flooding in the U.S. and around the world. For example, Hurricane Sandy brought a record storm tide to New York City in October 2013, flooding more areas than otherwise would have been inundated, since the sea level in lower Manhattan had climbed by about a foot during the 20th century. A study published earlier this year found that coastal flooding could affect nearly 5% of the global population on an annual basis, with expected yearly losses of up to 9.3% of GDP by the year 2100, unless significant actions are taken to better protect low-lying urban areas.

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