Although there is a combination of factors behind the numerous jellyfish that reach vacation havens like the Mediterranean coast, climate change is also partially to blame. Warmer sea temperatures are opening up new areas where jellyfish can reproduce, and increasing the availability of their favorite food: plankton.

Prized for their superior sound quality, an original Stradivarius can sell for millions of dollars. Yet, extreme weather events, such as unusually violent storms, are killing millions of trees, putting at risk the famous wood in the Paneveggio forest, in northern Italy. Replanting trees won't help much in the short term. A spruce has to be at least 150 years old before it can become a violin.

On very hot nights, people sleep worse, especially in big cities. By 2050 European metropolises may experience temperatures around 3.5 degrees Celsius warmer in summer. It not only affects sleep, but also mood, productivity and mental health. The only way to escape is to move to smaller towns and settlements, where the nights are cooler since there are fewer buildings and more greenery.

Spring is starting earlier in the year due to global warmer temperatures — bad news for allergy sufferers. With a longer frost-free season, plants have more time to grow, bloom and produce pollen. Therefore, pollen will freely roam around much earlier, which will make the suffering season longer and the annual pollen load greater. Will it be the century of masks for air pollution and allergies?

Heat not only makes us sweat; it also affects our health. By the end of this century three-quarters of the world's population is expected to be exposed to dangerous and deadly heat waves. Rising temperatures mean an increase in diarrheal diseases, as it's easier for bacteria to multiply in warm food and water. Mosquito numbers will also likely go up, along with the spread of diseases like malaria.

Soil in the region around the North Pole is increasingly thawing in the summer months, with dramatic local and global consequences. Warmer temperatures cause floors to become unstable and houses and roads to crack, and leads to many more insects. Moreover, if permafrost — frozen soil — melts, it will release CO2 and methane gases that could further exacerbate global warming. It's a vicious circle.

Temperature can influence the sex of several species. For sea turtles, the heat of the sand where the eggs are incubated determines the sex of the newborn. Low temperatures benefit male turtles, while females develop better in warmer areas. Researchers have found that over 99% of turtle hatchlings in northern Australia are already female, making it difficult for the species to survive.

The first strike of the day kicked off in the French Pacific territory of New Caledonia. Islanders have worked hard in recent years to protect the vital coral reefs that surround the archipelago. However, rising sea levels are placing every island nation in peril.

Students in the Solomon Islands, which comprises hundreds of islands in the South Pacific, skipped school on Friday morning to call attention to how climate breakdown threatens their country.

The first major protests of the day started in Australia, where demonstrators want the government and businesses to commit to a target of zero net carbon emissions by 2030. More broadly, they are seeking for world leaders to commit to real change at an upcoming UN Climate Action Summit.

Thai students joined the global movement outside of the Ministry of Natural Resources and the Environment in Bangkok. Thailand, as part of the Mekong River basin, has already felt the effects of catastrophic flooding and coastal erosin.

Demonstrators gathered in Palangka Raya, on the Indonesnian island of Borneo, which is currently covered in smog from forest fires. Borneo is already feeling the devastation from deforestation due to palm oil farming, which has hurt the local human populations as well as dramatically reduce the habitat for orangutans.

Bangladeshi school students and other climate activists took to the streets of the capital Dhaka. Bangladesh is a major hub for the garment industry, which on top of forcing workers into sweatshop conditions, is one of the most polluting industries on earth.

An estimated 100,000 people joined a climate rally in the government district in central London. Similar marches were held in dozens of other European cities, including Paris, Stockholm and Helsinki.

Protesters got started before dawn in Germany, with demonstrations planned for almost every major city. Here in Frankfurt, climate strikers blocked rush hour traffic in the city's central Baseler Platz, unperturbed by the chorus of car horns.

Students in the Old Town Square in Prague, Czech Republic, called on their leaders to lower carbon emissions and enact better climate protection. The Prague demonstration was one of 5,000 planned around the world.

Activists in Nairobi, Kenya, called for an end to the government's plans to open new coal mines. They want more support for renewable energy sources across the country.

Greta Thunberg, the Swedish teenager who started the worldwide climate strike movement, led a major demonstration in New York City. Tens of thousands of people filled Lower Manhattan to march with the 16-year-old from Foley Square to Battery Park. "I hope this will be another social tipping point that we show how many people are engaged," she told Agence-France Presse.