1. It's Warming.
Right now, the Earth’s surface temperature is about 1.3° Celsius hotter than industrialization in the late 1800s.
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Climate Science Basics:
Floods, wildfires, tropical storms, drought.
Food crisis, water shortage, displacement, conflict. The impacts of the climate crisis are already everywhere and affect people deeply – hitting harder those in most vulnerable areas or social conditions, who have often contributed the least to worsening this emergency.
The science is clear:
the planet is heating and we are causing it. And it is also up to us to solve this crisis, ensuring a liveable and equitable future for everyone.
Earth has always experienced natural warming and cooling cycles. What we are seeing now is different and concerning. Climate scientists say “every decade since 1850 has been warmer than the last four decades”. The ten hottest years have all happened since 2000, because of human activity.
Rising temperatures don’t just mean hotter weather. Earth’s climate is complex. Even small rises in global temperature can lead to big changes. These changes can have dangerous effects on entire ecosystems and mean life and death for millions of people.
The global 2015 Paris Agreement set 1.5ºC as the critical heating limit we can’t afford to cross. According to scientific research (and our People’s Dossier on 1.5˚C), surpassing this will trigger climate “tipping points”. Meaning, we will start seeing “sudden, permanent, and dangerous changes” with serious effects on humanity if we don’t stop global heating right away.
And the reality is dire: a report by the Intergovernmental Panel on Climate Change (IPCC) shows that at our current pace, the world could very well get 1.5˚C hotter as soon as 2040. That’s less than 20 years away and within most of our lifetimes. In fact, 2024 became the first year that was more than 1.5 °C hotter than pre-industrial levels. Now, even if all countries deliver on their promises to cut emissions by 2030, we’re still on track for a 2.7˚C rise by 2100.
Scientists warn that if we reach a 2.7˚C rise, many parts of the world will face “unbearable heat” and even more unpredictable weather. Wildlife will vanish, food shortages will occur, cities, and other human systems will be damaged.
GRAPH: NASA TIME SERIES: 1884 TO 2021
Caption: Interactive time series showing average planetary temperature, from 1884 to 2021. Source: NASA’s Scientific Visualization Studio (NASA Time Series)
2. It’s Us.
Humans are causing climate change by burning fossil fuels, the science is clear.
Before the 1700s, our atmosphere had around 280 parts per million (ppm) of carbon dioxide (CO2). This was the level of carbon that life on Earth, including humans, had adapted to. But things started to change when parts of Europe and North America began burning coal, oil, and gas to power transport and factories – what is known as the “Industrial Revolution”.
Since then, the use of fossil fuels spread very quickly worldwide, making carbon in the atmosphere shoot up. In 2002, we had 365 parts per million of CO2, and nearly 25 years later we’re now over 420 ppm. Many climate scientists consider 350 ppm the safe upper limit for atmospheric CO2 to maintain a stable climate. And we’ve already exceeded the threshold for climate safety by a significant margin. Learn more about why this matters at 350.
As the use of fossil fuels spreads through the world, the amount of carbon in the atmosphere is skyrocketing. In 2002 we were at 365 parts per million of CO2 in the atmosphere, and just two decades later we’re crossing 420 ppm.
Another factor in the rapid rise in other dangerous greenhouse gasses like methane is that wealthier countries’ demand for meat and dairy has driven more livestock farming. Agriculture now causes about 15% of all emissions.
Burning fossil fuels remains the major issue because carbon dioxide remains in the atmosphere much longer than methane and other greenhouse gasses. In 2021, it accounted for 89% of the energy sector’s greenhouse gas emissions and in 2024, global fossil CO2 emissions were the highest ever recorded. Keeping fossil fuels in the ground is the most important step we can take to stop climate change.
Source: NOAA
3. We’re Sure.
There is no real debate about the basic science of climate change: 99% of scientists agree that humans are causing it.
We’ve known since the 1890s that more CO2 in the atmosphere heats the planet. Groups that stand to lose money often attack climate science. Fossil fuel companies, in particular, spend millions to create doubt about climate change.
Oil and gas giants, Exxon and TotalEnergies have known about climate change since the 1970s. They understood that taking action could hurt their profits. So they have been covering up the truth, funding lies and deception, and misleading shareholders and the public for decades.
Between the 2015 Paris Agreement and 2019, the top five oil companies spent a combined US$1 billion on misleading climate-related branding and lobbying. Even today, they are actively fighting to maintain fossil fuels for decades to come. Their greed, combined with government inaction, has created our current crisis. We now live in a world where billionaires hoard extreme wealth, while the rest of us face rising costs, worsening inequality, and a climate crisis. Just 1% of people own more wealth than 95% of us combined, all while destroying our planet.
Believing these profit-driven companies and denying the climate crisis means ignoring established scientific facts and generations of Indigenous, local, and traditional knowledge. Local communities and Indigenous Peoples manage 50% or more of the world’s land, including 54% of the world’s remaining intact forests. Their customary practices ensure that lands often see lower rates of deforestation and degradation than lands managed by public or private entities. As Brazilian Indigenous leader Ailton Krenak explains, “People think climate change is something for the future, but we live inside our forests for a long time. […] We live on the Earth through the constant interaction between people and nature.”
The ‘debate’ is OVER. Scientist march for action on climate change. Photo credit: Road to Paris
4. It’s Bad.
1.3˚C of warming has already resulted in devastating impacts for people and the planet. And these impacts hit some of us harder.
According to the latest IPCC report on Impacts, Adaptation and Vulnerability, around 3.3 to 3.6 billion people live in contexts that are highly vulnerable to climate change. The report also says that 50-75% of the world population can be exposed to periods of “life-threatening climatic conditions” by 2100, especially connected to exacerbated heat and rainfall.
Food production is very negatively impacted by global heating. Grain yields, for example, face a decrease in production. Food insecurity and water shortage can lead to humanitarian crises, conflict and displacement, unequally affecting different areas of the world – disproportionate impacts are being witnessed especially in parts of Africa, Asia, Central and South America, small islands and the Arctic.
Seasons are changing and becoming more unpredictable, making it harder for farmers to know when to plant and harvest. Projections show that even if we stay close to 1.5°C by 2100, 8% of today’s world’s farmland will become unsuitable. The fish production in tropical areas of Africa will also suffer a reduction that can go from 3% up to 41% – deepening the food crisis as marine life is the main source of protein for about one-third of people living in the continent.
Social inequalities within and across countries will get deeper as the impacts of the climate crisis hit harder. Vulnerable social groups, “including women, young people, the elderly, ethnic and religious minorities, Indigenous People, and refugees” are more likely to suffer harder from the impacts of the climate crisis – being more exposed to food and water scarcity, poverty, health issues, conflict and violence connected to climate change.
The IPCC states the difference between 1.5˚C and 2˚C of global temperature rise could mean well over 10 million more migrants from sea-level rise. People all over the world have the right to seek the best possible conditions to live, and to thrive. But involuntary displacement due to climate-related events (mainly floods and storms) has already displaced more than 20 million people per year since 2008.
Adaptation to these and other new realities emerging from climate chaos is inevitable and crucial, but it also highlights inequities around the world. The efforts have been fragmented and unevenly distributed. According to scientists, “substantial adaptation gaps still exist, especially among populations with lower income. At the current rate of planning and implementation, these adaptation gaps will continue to grow [and] the world is currently under-prepared for the coming climate change impacts, particularly beyond 1.5°C global warming”.
Climate change science leaves no room for doubt. New studies and reports confirm what we’ve known for decades: increased frequency and severity of extreme weather events is a result of climate change. It’s bad for all of us — and for some of us, even worse.
Caption: Interactive map showing how climate change affects extreme weather around the world. Source: CarbonBrief
Extreme Heat
One of the clearest findings of climate science is that global warming amplifies the intensity, duration and frequency of heat waves, drought, and wildfires.
Caption: In 2022, Europe has gone through extreme temperatures, with London (UK)
reaching record
breaking 40˚C during summer, wildfires catching up on parts of Spain and Portugal and tens of
thousands people displaced. Photo credit: NOAA
Our planet’s atmosphere and oceans are heating up ten times faster than anytime in the last 65 million years. This has been particularly noticeable in the past 20 years.
Caption: Map highlighting in brown the regions where droughts are expected to become worse as a result of climate change. Source: IPCC.
Warming is increasing the severity of drought. A warmer atmosphere sucks more water from the soil, increasing the likelihood for drought conditions and increased plant stress. The UN has warned that "over 50 million people in Eastern Africa should face acute food insecurity" in 2022 due to four consecutive years of short rainfall. The drought was the worst in 40 years for many countries in the region. If we don't cut emissions substantially and immediately, the prognosis is that "a third of global land areas are projected to suffer from at least moderate drought by 2100." Read more about the role of fossil fuels on causing droughts.
Wildfires are also an indicator of our rapidly warming atmosphere. The latest IPCC report states that "a quarter of the world’s natural land now sees longer fire seasons as a result of increases in temperature, aridity and drought".
In 2021, a 30% increase in aridity of the soil and record-breaking temperatures have caused Turkey an abrupt increase in the extension of forests burnt. And wildfires have been raveging in California, in the US, for longer and with increased intensity in the last years. In 2020, more than 200,000 fires were spotted mainly in the Pantanal, Cerrado and Amazon regions of Brazil – 15% more than in the previous year and likely to be more frequent. Another consequence is heatwaves, read more here.
Ocean Warming + Acidification
While record-breaking warming is being felt on land, most of the extra heat energy being trapped in our atmosphere is being stored deep into our oceans causing rapid changes and the decline of key ecosystems.
Caption: Summer Arctic sea ice extent is shrinking by 12.6% per decade as a result of global warming. Source: NSIDC/NASA
Since 1955, more than 90 percent of the energy trapped by the atmosphere as a result of increased greenhouse gasses has been absorbed into the oceans – and the ocean's warming rate has increased significantly over time.
Melting Ice
Due to warming of the oceans and atmosphere, the amount of ice on Earth is declining — from glaciers to the Arctic and Antarctic. This is driving sea level rise, reducing the Earth’s ability to reflect heat energy back out to space, and endangering unique ecosystems.
Since satellite records began 4 decades ago, the Arctic’s sea ice has been in dramatic decline, losing on average 13% of its mass each decade. The entire Arctic region is undergoing drastic changes, threatening vital habitat for countless species and the livelihoods of many Indigenous communities. Severe “snowmageddon” winters are very likely linked to the rapidly increasing polar temperatures, with deadly summer heatwaves and intense flooding probably also linked.
The Antarctic ice sheet is also undergoing changes as ocean temperatures increase, albeit more slowly than the Arctic. As the world’s largest store of freshwater, Antarctica has the potential to intensely contribute to sea level rise: close to zero for up to 1.5 degrees Celsius heating, but quickly jumping to at least 2 meters if we pass 2 degrees Celsius. The difference we can make now by keeping fossil fuels in the ground is astounding: if we act now, we can keep the Antarctic ice sheet largely intact.
Glaciers are also very sensitive to temperature change and as a result of climate change, and all around the world they are in irreversible retreat. The decline of glaciers in the Himalayas, Andes, Arctic, New Zealand Southern Alps and elsewhere pose significant costs and threats to people and wildlife, as they provide an important year-round source of water to many cities and ecosystems around the world.
Warmer oceans = More sea level rise
As water heats up, it expands. This simple phenomena, alongside the influx of water into the oceans from melting ice in the polar regions and the world’s glaciers, is driving rapid sea level rise. It only takes a small amount of sea level rise to cause dramatic damage and change — as king tides and storm surges sweep further inland. Read more about tropical cyclones , which get fuelled by warm waters.
Caption: In 2022, leaders of 15 low-lying Pacific island nations declared climate change their “single greatest existential threat”. In 2014, Fiji became the first nation to relocate a community because of rising sea levels when salt water invaded Vunidogoloa. Photo credit: Forest Woodward, Matagi Mālohi movie
Projections show that "extreme sea level events that previously occurred once in 100 years could happen every year by the end of this century" in several places around the world. The current rate of sea level rise is around 3.7mm/year, but this rate is growing over time, on top of year-to-year ups and downs.
If we keep fossil fuels in the ground and limit heating to less than 2°C, we have a chance of limiting sea level rise to about 50 cm by 2100. With 37% of the world’s population living near the coast, the stakes are high.
Mass global coral bleaching events
Prior to the 1980s there were no signs of any global coral bleaching events for thepast ten thousand years, past ten thousand years, and probably much longer. It’s only in the last 35 years that this has started to occur. From the Great Barrier Reef to the Andaman Islands of the Indian Ocean, what were once bright colorful coral reefs full of life have turned bleached white then murky brown as they’ve died and become covered in algae. (Read more about our Coral Reef Crime Scene campaign.)
Reefs support approximately 25% of all marine species. A massive coral die-off risks the lives or livelihoods of one billion people around the world, who benefit either directly or indirectly from these ecosystems. If greenhouse gas emissions remain unchecked, we will kill off most of the world's coral reefs within decades.
Extreme Storms + Flooding
Storms, hurricanes and typhoons have always happened, but because of human-caused climate change, they are now causing heavier rainfall, more flooding, bigger storm surges and blowing with stronger winds.
According to IPCC AR6, "an increased intensity and frequency of record-breaking daily rainfall has been detected for much of the land surface where good observational records exist, and this can only be explained by human-caused increases in atmospheric greenhouse gas concentrations." The connection is clear: for every extra degree of warming, the atmosphere holds about 7% more water vapor – and more water vapor in the atmosphere means more energy, fueling precipitation and altering the areas where the storms occur.
In 2022, 33 million people suffered from deadly floods in Pakistan after monsoons struck the country with rainfall almost 800% higher than usual. In 2021, the waters took the streets of towns in Germany and the Netherlands in one of the most severe rainfalls in one century, taking more than 200 lives. In 2016, the unusually warm waters in the Caribbean lead to the incredibly rapid intensification of Hurricane Matthew, turning it from a tropical storm into a Category 5 in just 36 hours and causing havoc in Haiti, Cuba, the Bahamas and the Southeastern United States as it progressed.
The cost of burning more fossil fuels is very real — it will make storms, hurricanes, typhoons and cyclones more deadly and costly. Keeping fossil fuels in the ground is the best way to protect people from untold destruction. Read more about the role of fossil fuels on causing floods .
Human health
Climate permeates all aspects of our lives, the consequences of a warmer planet will impact our well-being in several ways – affecting vulnerable communities the most.
Climate change is considered to be one of the biggest risks to human health – and according to the World Health Organization it is likely to cause around 250,000 deaths every year between 2030 and 2050, especially from malnutrition, malaria, diarrhea and heat stress.
Caption: Climate change impacts health both directly and indirectly. Source: WHO
It is harder to grow, transport and store food in a warmer climate, and climate change will also impact water quality and availability deeply. These trends will hit poor populations the hardest, deepening inequality across the world and within countries. According to the last IPCC report, the number of people suffering from hunger in 2050 will vary from 8 million to 80 million, with populations in Sub-Saharan Africa, South Asia and Central America being the most severely affected. Also, "globally, 800 million to 3 billion people are projected to experience chronic water scarcity due to droughts at 2°C warming, and up to approximately 4 billion at 4°C warming."
One of the most obvious consequences of a warming climate is also heat stress. By 2100, the percentage of the world population exposed to deadly heat will certainly increase – from today's 30% to 48-76% – but the numbers depend on how much we are able to cut emissions. In Europe, for example, the number of people at risk of heat stress will be 2 or 3 times higher in a world 3°C warmer if compared to 1.5°C. Heat stress is connected to dehydration, organ failure, cardiovascular disease and even death, and also affects most vulnerable populations like women, elderly and poorer communities the hardest.
Caption: Female Aedes albopictus mosquito capable of spreading Zika virus. (Photo: James Gathany/CDC) Source: PHIL
The increase in temperatures is also expanding the areas in which mosquito-borne diseases like Zika, malaria and dengue fever are common. A report by Lancet published in 2022 found that "the periods when malaria could be transmitted became 32% longer in upland areas of the Americas and 15% longer in Africa", if compared with the 1950s. The chances that someone is infected by dengue also increased, by 12% over the same period. And the lPCC AR6 shows that "an additional 1 billion people are projected to be at risk of dengue exposure by 2080 under a mid warming scenario, and 5 billion under a high warming scenario."
Extreme weather events (floods, hurricanes, heatwaves or wildfires) are linked to increased violence and "can trigger post-traumatic stress disorder, anxiety, and depression". More and more people will be exposed to losses of homes, businesses and lives due to the more extreme weather conditions and "all of these have profound, often long-term effects on mental health". Organizing and uniting our forces to pressure for immediate climate action is the best way to ensure future generations will have the chance to thrive.
Shifting seasons, habitats & climatic zones
The warming of the atmosphere is changing the timing of seasons, the distribution of habitats and moving warmer climate zones toward the poles.
A study based on 976 plants and animals found that 47% of them had suffered local extinctions as a result of climate-induced changes. And the latest IPCC report on Impacts, Adaptation and Vulnerability is very clear: "threats to species and ecosystems in oceans, coastal regions, and on land, particularly in biodiversity hotspots, present a global risk that will increase with every additional tenth of a degree of warming."
More frequent, longer and more severe heatwaves, wildfires, droughts and flooding seasons are putting many species of plants and animals in distress and pushing them beyond their tolerance thresholds or ability to adapt. And it's not as 'simple' as, for example, polar bears disappearing – ecosystems are interconnected, and the extinction or migration of one single species can have unexpected and unpredictable cascading effects. All that affects humans, as the disruption of nature reduces its "ability to provide the essential services that we depend on to survive – such as coastal protection, food supply or climate regulation via carbon uptake and storage."
About half of the species in the world have already been affected in some way. Animals and plants are already changing their habitats more towards the poles, to higher altitudes, or to deeper ocean waters to run away from extreme weather. Right now, about 12% of the 8 million species of animals and plants on Earth are at risk of extinction and facing a massive, quick and unprecedented decline which is also due to climate change. And studies show that as global heating goes up, those numbers will become worse: with 2°C by 2100, about 18% of all plants and animals that live on land will be at risk of extinction but if the world warms up to 4.5°C, "about half of all plant and animal species that we have records for will be threatened".
Nature's conservation goes hand in hand with the climate crisis – both suffering its results and being part of the solution for ensuring a livable future for human beings. Scientists say that “by restoring degraded ecosystems and effectively and equitably conserving 30 to 50 percent of Earth’s land, freshwater and ocean habitats, society can benefit from nature’s capacity to absorb and store carbon.”
Climate change is already changing seasons, affecting habitats and shifting climatic zones, pushing species to extinction, and farmers to hardship. Keeping fossil fuels in the ground is the best way to protect important habitats and livelihoods.
5. We Can Fix It.
The basic facts of climate crisis are grim: the vast majority of fossil fuel reserves need to stay in the ground for us to stay below 1.5°C of heating, and fossil fuel companies aren’t going to do that without a fight.
Here’s the good news:
The climate crisis is happening now and to all of us, but it is not felt equally by everyone. It exacerbates inequities and cuts across all aspects of our lives: food, jobs, health, human rights. The only real solutions are those rooted in justice and putting people and communities first. A world beyond fossil fuels is also a world with more equitable gender, racial, migrants, workers and social rights – within and across borders.
At 350.org we believe and fight for a safer climate and a better future where everyone can thrive – and we need you with us in this fight!