26 facts that bring home the reality of climate change

...and four that offer hope.
Photograph by Paul Nicklen, Nat Geo Image Collection
By Jonathan Manning, Simon Ingram
Published 30 Oct 2021, 08:00 BST, Updated 5 Nov 2021, 12:12 GMT

UNDERSTANDING the many challenges facing our world on the eve of COP26 isn't easy. It's hard to understand a water crisis when some countries are flooding. It's hard to appreciate the Arctic ice disappearing when the winter news is filled with stories of extreme weather events.

But it's this instability of the climate, caused by the slow heating of our world, that is perpetuating these extremes. The consequences can devastate economies, infrastructure and political stability – a situation described in 2011 by UN Secretary General Ban Ki-Moon as an 'unholy brew'. In the same speech Ban called climate change the 'defining issue of our time'. Evidence for that is simply down to the facts. 

Mastodons and woolly mammoths roamed the Earth the last time the concentration of carbon dioxide (CO2) in the atmosphere reached today’s levels, at 417 parts per million, according to the National Oceanic and Atmospheric Administration. Scientists say levels of CO2, which as a greenhouse gas traps heat and causes global warming, are now comparable to the Pliocene Age, between 4.1 and 4.5 million years ago, when sea level was about 24 metres (78 feet) higher than today and the average temperature was nearly 4 degrees Celcius (°C) (7 degrees Fahrenheit (°F)) warmer. 

Earth's seen 20,000 years of change in 170

Since 1850, human activities have driven up CO2 concentrations by 48%. It took 20,000 years for levels to rise naturally by this extent, from the Last Glacial Maximum, when the Laurentide Ice Sheet covered the northern third of North America as far south as New York City, some 21,500 years ago.

July 2021 was the hottest month ever recorded

First place is the worst place in this race, as July 2021 secured its ranking as the hottest month ever recorded since records began 142 years ago, according to the National Oceanic and Atmospheric Administration. Around the world, the combined land and ocean-surface temperature was 0.93°C (1.67°F) above the 20th-century average of 15.8°C (60.4°F).

Sea ice melts from white into turquoise pools off Baffin Island, Nunavut, Canada. Between 1979 and ...

Sea ice melts from white into turquoise pools off Baffin Island, Nunavut, Canada. Between 1979 and 2018, the proportion of sea ice five years old or more in the Arctic has reduced from 30% to 2%.

Photograph by Brian Skerry, National Geographic Image Collection

Tree planting isn't enough

A noble and regenerative activity for sure – but relying on it to absorb enough carbon emissions to achieve ‘net zero’ by 2050 would require 1.6 billion hectares of new forests. That’s five times the size of India, or more than all the farmland in the world, says Oxfam

UK rain is on the rise...

The UK is suffering more extreme weather events as the climate changes. This summer alone, Greater London has seen 48% more rainfall than the city’s long-term average, and increases of a similar scale have been recorded in Hampshire (up 49%), Surrey (up 54%) and West Sussex (up 52%).  Last year was the UK's fifth wettest year since 1862, with 116% of the 1981–2010 average and 122% of the 1961–1990 average rainfall, according to the International Journal of Climatology.

...and so are heatwaves

The Met Office issued its first ever amber heat warning for the UK in July 2021, and Northern Ireland broke its all-time temperature record on July 21, as the mercury soared to  31.3°C at Castlederg.

Spring is coming earlier

Nature is racing to keep pace with the earlier springs and later autumns brought by rising temperatures. The ‘first leaf’ date for the pedunculate oak in the UK was 10 days earlier in 2020 than the average for 2000–09, according to the International Journal of Climatology

The dry, salt-crusted Lake Poopo. Poorly irrigated land, logging or evaporation can cause desertification. The amount ...

The dry, salt-crusted Lake Poopo. Poorly irrigated land, logging or evaporation can cause desertification. The amount of the Earth that is becoming arid grows each year.

Photograph by Maurico Lima, Nat Geo Image Collection

Antarctica loses an Everest of ice every year

Antarctica is losing 151 billion tonnes of ice per year, roughly equivalent in weight to the rock that makes Mount Everest, according to NASA’s Grace Follow-On satellite.

The homes of 200 million people will be below sea level in 70 years

200 million people in the world, more than three times the UK population, will live below the tideline by the end of this century if levels continue to rise, according to Nature Communications. Sea levels have risen by 178mm (7 inches) since 1900 and are rising by 3.4mm per year. They reached record heights in 2020 for the ninth consecutive year – about 91.3mm (3.6 inches) higher than the 1993 average, when satellite altimeter records began. Sea levels rise because heat stored in the ocean causes water to expand, while melting ice sheets and glaciers are adding to the volume of water. China, Bangladesh and India are particularly vulnerable to rising sea levels, coastal storm surges and flooding, as are the Netherlands and parts of the UK.

Deserts are growing

Each year, more than 12 million hectares of land are lost to desertification, land degradation and drought, according to the UN – a surface area equivalent to the entire arable land of Germany.

Fires are getting more frequent – and worse

Wildfires, from Australia to California and Greece, are raging for longer and spreading farther than ever before, says the United Nations (UN), which calculates that the blazes devastated roughly 30 million acres of land from 2018-2020, 10 times the size of Yorkshire.

A million species are at risk

A chilling number of Earth's other denizens, including 40 percent of all amphibians known to science (about 3,200 species) is under threat due to human impact, according to the UN. Climate change, pollution, deforestation, overfishing, development, and invasive species are putting biodiversity in peril.

			A fire rages in Brazil's rainforest, near Maranhao at night.
A fire rages in Brazil's rainforest, near Maranhao at night.


Photograph by Charlie Hamilton James, Nat Geo Image Collection

Plastic production is speeding up

Plastic production and use is forecast to double over the next 20 years, and quadruple by the early 2050s, warns the Heinrich Böll Foundation, despite the fact that greenhouse gases, such as CO2 and methane, are released at every stage of plastic’s lifecycle – from the extraction and refinery of oil to the manufacturing process and end-of-life disposal and incineration. Every year, 17 million barrels of oil are used to make plastic and 13 million tonnes of plastic leak into the ocean, calculates the UN.

75 million kids suffer food insecurity

At least 155 million people, 2.3 times as many as live in the UK, were pushed into acute food insecurity in 2020 due to extreme weather, as well as conflict and economic shocks, says the World Food Programme. Among those suffering were over 75 million children under the age of five who displayed the symptoms of stunted growth. “Weather extremes will continue to exacerbate acute food insecurity in fragile economies,” says the WFP.

Deaths from heatwaves are up – a lot

Blistering temperatures are proving fatal, with The Lancet reporting that during the past 20 years there has been a 53·7% increase in heat-related mortality in people older than 65 years. Globally, this caused the premature deaths of 296,000 people in 2018 alone, enough to fill all the seats at Wembley Stadium three times over.

The concept of tipping points is scary

What many don't realise about the warming of the present Earth is that once we pass a certain threshold, physics takes over. This is at least true for the ice sheets, which – once they hit a rate of melting – can no longer sustain their mass. Known as the surface mass balance (SMB) passing this tipping point means that the ice sheet can no longer sustain its colossal mass based on the amount it is replenished by precipitation, and begins an unstoppable and accelerating decline humans are powerless to stop. With strong mitigation – limiting global temperature rise to ideally 1.5 degrees C, the levels agreed by nations administering the Paris Agreement – the ice sheets will continue to lose mass, but won't pass this critical tipping point. Without it, in a high emissions scenario, scientists are unsure when that tipping point may be hit. But based on the last century, it doesn't look good. 

It's no good just having cold winters to replenish ice levels. White ice – the long term, multi-year ice – reflects sunlight, helping to stave off warming. Thin, black seasonal ice doesn't do that nearly as effectively. Which is why the decline in Arctic sea ice is particularly alarming. According to the IPCC, between 1979 and 2018, the amount of sea ice five years old or above dropped from 30% to 2%. 

A hurricane batters the Florida coast. Scientists believe hurricanes are becoming more intense and moving more ...

A hurricane batters the Florida coast. Scientists believe hurricanes are becoming more intense and moving more slowly due to climate change, increasing their impact on human settlements. 

Photograph by Otis Imboden, Nat Geo Image Collection

Climate change is causing extreme weather events

Studies conducted between 2015 to 2020 have shown the ‘fingerprints’ of climate change in 76 floods, droughts, storms, and temperature anomalies, as well as dramatically increasing the risk of wildfires in 114 countries. 

Dangerous diseases are on the move 

Climate change is accelerating the spread of infectious diseases, such as dengue fever and malaria, creating conditions in more regions where the infections can thrive. In 2018, dengue had expanded by as much as 15% compared to a 1950s baseline, according to medical experts at The Lancet. (Related: seven warmer weather diseases climate change may bring to the UK.)

All Earth faces warming

Nowhere on the planet is spared the impact of climate change. In 2020, record temperatures were recorded in Belarus, Belgium, Estonia, Finland, France, Kazakhstan, Lithuania, Luxembourg, the Netherlands, Norway, Poland, Spain, Sweden, Switzerland and Ukraine, as well as Japan, Mexico, Russia, Seychelles, while the town of Blenheim, New Zealand reported a record-breaking 64-day dry spell, according to the National Centres for Environmental Information.

Antarctica saw t-shirt temperatures in 2020. The Arctic was sweltering

The eve of mid-summer’s day 2020 saw the warmest ever temperature recorded within the Arctic Circle – a crazy 38°C at Verkhoyansk, Russia. Similar warming is evident at the other end of the Earth, where, the Esperanza Station in Antartica reached 18.3°C (64.9°F) on February 6, 2020, the highest temperature ever recorded on the continent.

Coastal erosion stats are staggering

From permafrost thaws causing cliff collapse in Alaska to rising seas and reduced sediment flow in the Mississippi causing a mind-boggling football field sized area of land to be lost every hour from the Louisiana coast, the combination of a warming climate, extreme storms, sea level rise and human activities is literally taking the land from under us.  

The wealthy aren't so green

Between 1990 and 2015, the richest 1% of the world’s population were responsible for more than twice as much carbon emissions as the poorest 50% of humanity, calculates Oxfam. The estimated average carbon footprint of the world’s richest 1% could be up to 175 times larger than that of someone in the poorest 10%.

The Great Barrier Reef has suffered an apocalypse 

The Great Barrier Reef in Australia  is estimated to have lost half its corals since the 1990s as a sustained rise in ocean temperatures bleached them white and made them uninviting to its colonising organisms. It only takes a spike of 1–2°C in water temperature to have a devastating impact, says the International Union for Conservation of Nature (IUCN). Reefs cover less than 0.1% of the ocean floor, but are home to more than one quarter of all marine fish species.

One third of the most precious habitats are under threat

Vulnerable ecosystems are under threat from climate change, with the IUCN warning that 83 of 252 natural World Heritage sites are at risk, including the Pantanal Conservation Area of Brazil and the Cape Floral Region Protected Areas of South Africa.

EVs have a hidden cost

Electric cars may emit zero tailpipe emissions, but they still have a sizeable carbon footprint from their manufacturing process. One manufacturer's electric SUV has to drive anywhere between 29,000 miles (47,000km) and 90,000 miles (146,000km) – depending on whether it is recharged with wind power or a ‘global energy’ mix that includes electricity generated from fossil fuels – before its greenhouse gas emissions are lower than the petrol model. Walking, cycling and shared public transport offer greener travel options.

A humpback whale and her calf off Vava'u, Kingdom of Tonga.

Photograph by Brian Skerry, Nat Geo Image Collection

Renewables are on the rise

Despite demands for coal and gas on the rise, renewables are set to provide over half the increased demand for electricity in 2021. Renewables generation in 2021 is set to expand by over 8% – the largest year on year growth on record. The price is the energy they generate is also coming down, with the energy produced from renewable sources costing far less to produce than fossil fuel alternatives, with the cost of commissioning new solar, onshore and offshore wind plants falling by, respectively, 16 per cent, 13 per cent and 9 per cent in 2020

Some species are bouncing back

Long the poster creatures for human-catalysed extinction, whales – including blue whales and humpbacks – have seen populations rebound, with record numbers spotted in zones where they were historically depleted. With the increase in sustainably-managed ocean zones and the growth of marine protected areas (MPAs) there is hope that our relationship with Earth's 'life support system' may become less a battle of attrition, and more symbiosis.  

The ingenuity on display when the finalists for the inaugural Earthshot Prize were announced earlier this year are evidence that when applied – whether for profit or philanthropy – humans are ingenious enough to help reverse some of the damage our species has done. Whether creating robust strains of coral, treating waste water or removing the need to burn tons of charcoal a day with a simple solar powered gadget, humans could be as good at saving the environment as we are at impacting it. (Related: These ideas could help save the world.)  

The world is waking up

A 2020 survey by the Boston Consultancy Group found that from 3,000 participants across eight countries, 70% were more aware now than before COVID-19 "that human activity threatens the climate is and that degradation of the environment, in turn, threatens humans." The rise in climate activism amongst young people – thought to be amongst the biggest global movements ever – demonstrates a growing awareness of the threat to the future. This, coupled with the dip in emissions due to lockdowns and the knock-on realisation of the impact of our own activities, aside from the occurrence of the disease in the first place, means that more may be inspired to do more.

Editor's note: a date in the first fact concerning glaciation was clarified on 5/11/21.

National Geographic is committed to encouraging positive action at an individual level to help curb climate change. In the run-up to COP26, discover more ways we all can live lighter on the planet here.


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