First organized in 1970, Earth Day is a day set aside to remember and appreciate the Earth's environment, and our responsibilities and roles within it. Today, April 22, we observe the 45th annual Earth Day, and though many things have changed for the better, environmental challenges remain. In the past 45 years, the population of the Earth has doubled—75 percent of the people alive today were born after 1970—and the increased demand on our limited resources makes sustainable solutions even more important. Collected here are 45 images of our world from recent years, each a glimpse into some aspect of our environment, how it affects and sustains us, and how we affect it.
A view of our home planet, Earth, as seen from the Moon by the Apollo 11 astronauts on July 20, 1969, one year before the first Earth Day was held in 1970. #
A Pace College student in a gas mask "smells" a magnolia blossom in City Hall Park on Earth Day, April 22, 1970, in New York City.
The professor David Noone from the University of Colorado uses a snow pit to study the layers of ice in the glacier at Summit Station on July 11, 2013, on the Glacial Ice Sheet in Greenland. As the sea levels around the globe rise, researchers affiliated with the National Science Foundation and other organizations are studying the phenomena of the melting glaciers and its long-term ramifications. The warmer temperatures that have had an effect on the glaciers in Greenland also have altered the ways in which the local populace farm, fish, hunt, and even travel across land.
Joe Raedle/Getty Images
Mountains of used tires lay in a dump in the countryside in Sesena Nuevo, near Madrid, Spain, on September 24, 2014. The dump site in Sesena is a major environmental problem and was declared illegal back in 2003. It currently stores over 75 tons of tires. The company which ran it was penalized heavily, finally walking away. Now the regional government has started to process the tires in order to clear the area within approximately four years. Most of the material will be recycled for building materials, surfacing for roads, sports tracks, and children's playgrounds.
Pablo Blazquez Dominguez/Getty Images
A Hypsiboas picturatus frog (Imbabura tree frog) at the Jambatu Center for Research and Conservation of Amphibians in Quito, Ecuador, on October 15, 2013. The Jambatu Center manages some 40 species of amphibians, and has run successful breeding programs for some critically endangered species.
A Hindu devotee pushes foam away to make space for other devotees to worship the Sun god Surya in the polluted waters of the river Yamuna during the Hindu religious festival of Chatt Puja in New Delhi on October 30, 2014.
Eagles await transfer to a warm U.S. Fish and Wildlife warehouse after being rescued from the cold on January 11, 2008, in Kodiak, Alaska. They were among 50 eagles which dove into the back of an uncovered dump truck full of fish guts and became too wet to fly away.
A giant bucket-wheel excavator removes the first layer of soil for the expansion of the Jaenschwalde open-pit lignite coal mine on August 20, 2010, near Jaenschwalde, Germany. The Jaenschwalde mine feeds coal to the nearby Jaenschwalde power plant, which is one of the biggest single producers of CO2 gas in Europe. The area of northern Saxony and southern Brandenburg is scarred with active and former mines, and a large-scale project is underway to flood the massive pits and convert them into lakes for tourism.
Sean Gallup/Getty Images
A bloom of Noctiluca scintillans, a large, green marine dinoflagellate that exhibits bioluminescence when disturbed, was captured in photos taken on January 22, 2015, in Hong Kong, with a long exposure showing an eerie glow along the seashore. The luminescence, also called Sea Sparkle, is triggered by farm pollution that can be devastating to marine life and local fisheries, according to the University of Georgia oceanographer Samantha Joye. Noctiluca itself does not produce neurotoxins like other similar organisms do. But its role as both prey and predator can eventually magnify the accumulation of toxins in the food chain, according to the oceanographer R. Eugene Turner at Louisiana State University.
An armed ranger talks on his radio while guarding a white rhinoceros at the Imire Rhino and Wildlife Conservation Park near Marondera, east of the capital Harare, on September 22, 2014.
A man looks at a contaminated river in Cangnan county of Wenzhou, Zhejiang province, on July 24, 2014. Local authorities said the water in the river turned red after several buckets of red dye were misplaced near the riverbank and the local environmental protection administration did not find harmful substances in the water, local media reported. The picture was taken on July 24, 2014.
An aerial view shows a tract of Amazon rainforest which has been cleared by loggers and farmers for agriculture, near the city of Santarem, Para State, on April 20, 2013. The Amazon rainforest is being eaten away at by deforestation, much of which takes place as areas are burnt by large fires to clear land for agriculture. Initial data from Brazil's space agency suggests that destruction of the vast rainforest—the largest in the world—spiked by more than a third over the past year, wiping out an area more than twice the size of the city of Los Angeles. If the figures are borne out by follow-up data, they would confirm fears of scientists and environmental activists who warn that farming, mining, and Amazon infrastructure projects, coupled with changes to Brazil's long-standing environmental policies, are reversing progress made against deforestation. Environmental issues will be under the spotlight as a United Nations Climate Change Conference opens in Warsaw, Poland, on November 11. This picture was taken on April 20, 2013.
A father and son (left) on a makeshift boat made from styrofoam paddle through a garbage filled river as they collect plastic bottles that they can sell in junkshops in Manila on March 19, 2015. They earn three U.S. dollars a day. The Philippines will be observing World Water Day on March 22, a global event that focuses on finding access to clean and safe water.
NOEL CELIS/AFP/Getty Images
In this Thursday, January 6, 2011, photo, men stand next to the glowing embers of an underground coal fire in the village of Bokapahari in the eastern Indian state of Jharkhand, where a community of coal scavengers live and work.
A big stain of palm oil invades the shore of Taganga beach in Santa Marta, department of Magdalena, Colombia, on April 23, 2008, after 10 tons of oil were spilled from the production plant of Terlica. Residents of the area have said of seeing dead fish but the spokesperson of Terlica said the oil is biodegradable and won't harm the environment.
A view of land clearing for palm-oil plantation in Siak district on July 11, 2014, in Riau province, Sumatra, Indonesia. The Nature Climate Change journal has reported that Indonesia lost 840,000 hectares of natural forest in 2012 compared to 460,000 hectares in Brazil despite their forest being a quarter of the size of the Amazon rainforest. According to Greenpeace, the destruction of forests is driven by the expansion of palm oil and pulp and paper has increased the greenhouse gas emissions, pushing animals such as sumatran tigers to the brink of extinction, and local communities to lose their source of life.
Ulet Ifansasti/Getty Images
Heavy fog rolls by early in the morning near the Dubai Marina November 21, 2007. Fog across the United Arab Emirates has disrupted traffic and delayed many flights over the last few days.
Olive Ridley turtle hatchlings (Lepidochelys olivacea) sit in baskets and trays at the turtle camp La Gloria, before their release into the ocean in Tomatlan on November 15, 2013. Twenty years ago, Mexico's government implemented ecological plans to protect the sea turtles from being hunted for their leather and meat, and established conservation areas and a pay system for local residents to protect turtle nests. Millions of baby turtles hatch on the shores in November and December, according to an environmental group. It is estimated that in 2012, there were 20 million newborns. Hatching season is still underway, but officials say they expect there will be even more turtles born this year. This picture was taken on November 15, 2013.
Farmers plant grass to stabilize sand dunes at the edge of the Mu Us Desert in Lingwu, northwest China's Ningxia Hui Autonomous Region, on October 19, 2007. The need to protect the environment and conserve resources was vital to "the survival and development of the Chinese nation," the Chinese leader Hu Jintao said in an address during the Communist Party's 17th Congress.
Members of the glaciology unit of Peru's national water authority walk on the Pastoruri glacier in Huaraz, Peru, on Thursday, December 4, 2014. The glaciology unit is studying the measurement of ice thickness. According to Alejo Cochachin, the coordinator of the glaciology unit, the Pastoruri glacier retreated 576 meters between 1980 and 2014. Peru's glaciers have lost more one-fifth of their mass in just three decades, and the 70 percent of Peru’s 30 million people who inhabit the country’s Pacific coastal desert, depend on glacial runoff for hydropower and to irrigate crops, meaning their electricity and long-term food security could also be in peril. Higher alpine temperatures are killing off plant and animal species in cloud forests, and scientists predict Pacific fisheries will suffer.
A boy heats up a computer circuit board to retrieve metal that is used to make soldering wire in a makeshift workshop in Karachi on December 13, 2012.
A paddleboarder floats by Lone Rock on Lake Powell on March 29, 2015, near Big Water, Utah. As severe drought grips parts of the Western United States, a below-average flow of water is expected to flow through the Colorado River Basin into two of its biggest reservoirs, Lake Powell and Lake Mead. Lake Powell is currently at 45 percent of capacity and is at risk of seeing its surface elevation fall below 1,075 feet above sea level by September, which would be the lowest level on record. The Colorado River Basin supplies water to 40 million people in seven western states.
Justin Sullivan/Getty Images
The landscape glows immediately after the main fire front swept over in a fast run toward Lake Hughes on June 1, 2013, south of Lake Hughes, California. The 19,500-acre wildfire destroyed numerous homes overnight. Nearly 1,000 firefighters have been working in hot, dry conditions to establish containment lines around 20 percent of the fire so far.
David McNew/Getty Images
Fish lie dead in the harbor area of Redondo Beach, south of Los Angeles, California, on March 8, 2011. Millions of fish washed up dead early on Tuesday, puzzling authorities and triggering a cleanup effort.
A Kenya Wildlife Services (KWS) officer stands near a burning pile of 15 tons of elephant ivory seized in Kenya at Nairobi National Park on March 3, 2015. Fifteen tons is the largest amount of contraband ivory burned in Africa to date. The pile was offically burned by the Kenyan President Uhuru Kenyatta to mark World Wildlife Day and African Environment day. An average of 30,000 elephants are poached every year in Africa.
Carl de Souza/AFP/Getty Images
A rainbow is visible looking West from Palm Springs, California, on Monday, January 28, 2008, next to an array of wind turbines. Southern California has been hit with heavy rainstorms totaling more than four inches in some areas over a 24-hour period which has some experts on edge about the possibility of mudslides. Scattered showers are forecast for the next few days.
Bamboo logs are transported down the river Longai near Kanmun village, about 235 kilometers (146 miles) west from Aizawl, the capital of India's remote northeastern state of Mizoram, on January 2, 2008. This picture was taken on January 2, 2008.
Adelie penguins stand atop ice near the French station at Dumont d’Urville in East Antarctica January 22, 2010. Russia and the Ukraine on November 1, 2013, again scuttled plans to create the world's largest ocean sanctuary in Antarctica, pristine waters rich in energy and species such as whales, penguins, and vast stocks of fish, an environmentalist group said. The Commission for the Conservation of Antarctic Marine Living Resources wound up a week-long meeting in Hobart, Australia, considering proposals for two "marine protected areas" aimed at conserving the ocean wilderness from fishing, drilling for oil, and other industrial interests. This picture was taken on January 22, 2010.
Fire boat response crews battle the blazing remnants of the offshore oil rig Deepwater Horizon, off Louisiana, in this April 21, 2010, file handout image. The trial to decide who should pay for the 2010 Gulf of Mexico oil spill has been delayed by a week, to allow BP Plc to try to cut a deal with tens of thousands of businesses and individuals affected by the disaster. Less than 24 hours before the case was set to start in a New Orleans federal court, the U.S. District Judge Carl Barbier pushed back the date to March 5, 2012, from February 27, 2012.
Reuters/U.S. Coast Guard/Files/Handout
Oil and oil sheen are seen moving past an oil rig, top right, in the waters of Chandeleur Sound, Louisiana, on Wednesday, May 5, 2010.
A sea bird is mired in oil on the beach at East Grand Terre Island along the Louisiana coast on Thursday, June 3, 2010. Oil from the Deepwater Horizon has affected wildlife throughout the Gulf of Mexico.
The former church tower of the Village of Graun in South Tyrol sticks out of the partially frozen Lake Reschen reservoir in Northern Italy on November 29, 2008. The village was destroyed and the valley flooded in 1950, due to damming up the Etsch River to produce electricity.
In this photo taken on Friday, June 15, 2012, a pig eats from a trash-ridden creek that runs towards the conference center where the United Nations Conference on Sustainable Development, or Rio+20, takes place in Rio de Janeiro, Brazil. The throngs streaming into Rio for the Earth summit may be dreaming of white-sand beaches and clear, blue waters, but what they are first likely to notice as they leave the airport is not the salty tang of ocean in the breeze, but the stench of raw sewage.
Victor R. Caivano/AP
The LED screen shows the blue sky on the Tiananmen Square at dangerous levels of air pollution on January 23, 2013, in Beijing, China. The air quality in Beijing on Wednesday hit serious levels again, as smog blanketed the city.
Feng Li/Getty Images
A statue of China's late Chairman Mao Zedong is seen in front of buildings during a hazy day in Shenyang, Liaoning province, on May 7, 2013.
Rocinha favela, or community, the largest favela in Rio, stands behind a mountain in an aerial view on February 24, 2015, in Rio de Janeiro, Brazil. Rio marks its 450th anniversary on March 1 and is celebrating the event with a yearlong series of events including concerts, exhibitions, historical tours, soccer matches, fireworks displays, and other activities. The "Marvelous City" was founded in 1565 by the Portuguese and was the seat of power of the Portuguese Empire in the 19th century before serving as the capital of the Brazilian Republic until 1960. The city is Brazil's most popular tourist destination and will host the Rio 2016 Olympic Games, the first to be held in South America, next year.
Mario Tama/Getty Images
An enormous iceberg (right) breaks off the Knox Coast in the Australian Antarctic Territory on January 11, 2008. Australia's CSIRO's atmospheric research unit has found the world is warming faster than predicted by the United Nations' top climate-change body, with harmful emissions exceeding worst-case estimates. This picture was taken on January 11, 2008.
A man working at an illegal oil-refinery site pours oil under a locally made burner to keep the fire going, near River Nun in Nigeria's oil state of Bayelsa on November 27, 2012. Thousands of people in Nigeria engage in a practice known locally as "oil bunkering"—hacking into pipelines to steal crude then refining it or selling it abroad. The practice, which leaves oil spewing from pipelines for miles around, managed to lift around a fifth of Nigeria's 2-million-barrel-a-day production last year according to the finance ministry. This picture was taken on November 27, 2012.
Petro-Canada's Edmonton Refinery and Distribution Center glows at dusk in Edmonton on February 15, 2009. This picture was taken on February 15, 2009.
Homes with swimming pools are seen in the Palm Springs area, California, on April 13, 2015. The average daily-water usage per person in Palm Springs is 201 gallons, more than double the California average. California's cities and towns would be required to cut their water usage by up to 35 percent or face steep fines under proposed new rules, the state's first-ever mandatory cutbacks in urban water use as the state enters its fourth year of severe drought. Communities where residential customers use more than 165 gallons of water per person per day would have to cut back by 35 percent. This picture was taken on April 13, 2015.
A general view shows solar panels producing renewable energy at the photovoltaic park in Les Mees, in the department of Alpes-de-Haute-Provence of southern France, on March 31, 2015. The solar farm of the Colle des Mees, the biggest in France, consists of 112,780 solar modules covering an area of 200 hectares of land and representing 100 MW of power.
In this November 11, 2014, photo, policemen stand guard on the perimeter of a crater created by gold mining during an occupation of an illegal gold-mining camp as part of an operation to eradicate the camps in the area known as La Pampa, in Peru's Madre de Dios region. Less than a month before Peru plays host to global climate talks, the government sent a battalion of police into the southeastern jungles to dismantle illegal gold-mining camps. In addition to contributing to deforestation, the illegal alluvial gold mining contaminates the jungle with tons of mercury.
An elderly man tries to clean up his home in the flooded village of Devecser, 150 kilometers (93 miles) west of Budapest, on October 6, 2010. The dam of a sludge reservoir at an alumina factory owned by MAL Zrt burst on Monday, flooding parts of three villages and killing at least four people, the regional emergency unit said.
Scrapped high-emission vehicles are seen piled up at a dump site of a recycling centre, waiting to be dismantled, in Yiwu, Zhejiang province, on April 8, 2015. According to local media, the city of Yiwu is planning to get rid of approximately 22,000 highly polluting vehicles by the end of this year. This picture was taken on April 8, 2015.
Black-headed ibis fly over Moe Yun Gyi Wetland, in Bago Division, about 70 miles north of Yangon, on January 28, 2015. Myanmar has one of the world's richest and most diverse endowments of wildlife, but the campaigners fear the country's natural habitats are coming under threat as it begins to develop after years of isolation under military rule.