As the year comes to a close, it's time to take a look back at some of the most memorable events and images of 2015. Among the events covered in this essay (the last of a three-part photo summary of the year): Thick smog in Beijing raises “red alerts,” Canada elects a new Prime minister, Palestinian attacks surge in Israel, Chewbacca is arrested in Ukraine, the attacks in Paris, an Italian volcano erupts, and much more. Warning, some of the photos may contain graphic or objectionable content.
A building and a large screen are seen through thick smog in Beijing on December 8, 2015, as China's capital issued its first ever “red alert” for pollution.
Damir Sagolj / Reuters
Russian President Vladimir Putin (right) and U.S. President Barack Obama share a toast during the luncheon at the United Nations General Assembly in New York on September 28, 2015.
Mikhail Metzel / RIA Novosti / Reuters
Guillaume Rolland of France stands on the line during the Highline Extreme event in Moleson, Switzerland, on September 25, 2015. European best slackliners competed on six different lines ranging from 45 meters (148 ft) to 495 meters (1,624 ft).
Denis Balibouse / Reuters
A Palestinian boy sleeps on a mattress inside the remains of his family's house, that witnesses said was destroyed by Israeli shelling during a 50-day war in 2014, during a sandstorm in Gaza on September 8, 2015. A heavy sandstorm swept across parts of the Middle East on Tuesday, killing two people and hospitalizing hundreds in Lebanon and disrupting fighting and air strikes in neighbouring Syria.
Suhaib Salem / Reuters
A prototype of Google's own self-driving vehicle, during a media preview of Google's current autonomous vehicles in Mountain View, California, on September 29, 2015.
Elijah Nouvelage / Reuters
Robert Hooper, exhausted after several days with little sleep, hugs his dog Toby on his property that was burned by the so-called Valley Fire near Middleton, California, on September 14, 2015. The Northern California wildfire ranked as the most destructive to hit the drought-stricken U.S. West this year claimed one life and burned at least 400 homes to the ground, fire officials reported.
David Ryder / Reuters
Enthusiast Desirae Hepp, dressed as "Immortan Joe" from the movie Mad Max, poses for a portrait during Wasteland Weekend event in California City, California, on September 26, 2015.
Mario Anzuoni / Reuters
A tourist poses for photographs in front of the rising sun at a tourist resort in Bayingolin Mongol Autonomous Prefecture, Xinjiang Uighur Autonomous Region, China, on October 3, 2015.
China Daily / Reuters
Liberal Party leader Justin Trudeau kisses his wife Sophie Gregoire as he arrives to give his victory speech after Canada's federal election in Montreal, Quebec, on October 19, 2015.
Chris Wattie / Reuters
Residents wait for rescue helicopters in a residential area flooded by the Kinugawa river, caused by typhoon Etau, in Joso, Ibaraki prefecture, Japan, on September 10, 2015. At least eight people were killed after rivers burst their banks in cities north of Tokyo following days of heavy rain.
Kyodo / Reuters
Faculty members embrace as they are allowed to return to Umpqua Community College in Roseburg, Oregon, on October 5, 2015. The campus reopened to faculty for the first time since October 1, when armed suspect Chris Harper-Mercer killed multiple people and wounded several others before taking his own life at Snyder Hall.
John Locher / AP
An aid worker distributes bread and supplies to migrants at a transition camp September 7, 2015 in Magyarkanizsa, Serbia. Thousands of migrants had crossed into Hungary from Serbia near the town of Horgas.
Win McNamee / Getty
A Dutch volunteer tries to comfort a migrant moments after arriving aboard a raft at a beach on the Greek island of Lesbos on October 23, 2015.
Yannis Behrakis / Reuters
A woman from Syria waits to cross the border with Croatia near the village of Berkasovo, Serbia, on October 21, 2015.
Marko Djurica / Reuters
An Israeli soldier shoots a Palestinian holding a knife after he stabbed another Israeli soldier, seen kneeling, during clashes in Hebron, West Bank, on October 16, 2015. The Palestinian man wearing a yellow "press" vest and a T-shirt identifying him as journalist stabbed and wounded the soldier in the latest in a months-long spate of attacks.
Nasser Shiyoukhi / AP
Israelis practice shooting on a gun range in Jerusalem, Israel, on October 15, 2015. The Israeli Government issued police reinforcements across Israel following a wave of terror attacks across Jerusalem and the country.
Ilia Yefimovich / Getty
Vehicles sit stuck in a traffic jam near a toll station as people return home at the end of the weeklong National Day holiday in Beijing, China, on October 6, 2015. Fifty lanes (at bottom) vie for 25 toll gates, then constrict down to a five-lane bottleneck (at top).
China Daily / Reuters
Chewbacca under arrest in Ukraine. Policemen detain a person dressed as Star Wars character Chewbacca during a regional election near a polling station in Odessa, Ukraine, on October 25, 2015. The wookiee was detained for illegal election-day campaigning, according to local media.
Ihor Babak / Reuters
A boy displays the winners' medal given to him by Sonny Bill Williams of New Zealand after the Rugby World Cup Final against Australia at Twickenham in London, on October 31, 2015.
Henry Browne / Reuters
A panorama stitched from several images of the surface of Mars, taken by NASA's Mars rover Curiosity on Sol 1174 (November 25, 2015). Curiosity has now been exploring Mars for more than 3 years, Earth time.
JPL-Caltech / NASA
Afghan men argue outside of the main gate as violence escalates for migrants waiting to be processed at the increasingly overwhelmed Moria camp on the island of Lesbos on October 22, 2015 in Mytilene, Greece. Dozens of rafts and boats are still making the journey daily as thousands flee conflict in Iraq, Syria, Afghanistan and other countries.
Spencer Platt / Getty
Women practice yoga during a performance on a glass bridge in the Shiniuzhai National Geo-park in Pingjiang county, Hunan province, China, on November 5, 2015.
China Daily / Reuters
Rime ice extends several feet horizontally from a sign marking the summit of 5,774-foot Mount Adams, the second highest mountain in New England, on November 17, 2015, in northern New Hampshire. Monday's freezing fog and strong winds formed the rime ice, creating a winter wonderland above treeline in New Hampshire's aptly named White Mountains.
Robert F. Bukaty / AP
A shirtless Xavier Broseta, Executive Vice President for Human Resources and Labor Relations at Air France, is evacuated by security after employees interrupted a meeting with representatives staff at the Air France headquarters building at the Charles de Gaulle International Airport in Roissy, France, on October 5, 2015, accosting and tearing clothes from at least two executives in attendance. Air France confirmed in a meeting with staff that it planned to cut 2,900 jobs by 2017 and shed 14 aircraft from its long-haul fleet as part of efforts to lower costs, two union sources said.
Jacky Naegelen / Reuters
A 3-month old female giant panda cub is photographed at the Giant Panda Conservation Center at the National Zoo in Kuala Lumpur, Malaysia, on November 17, 2015.
Joshua Paul / AP
Big wave surfer Sebastian Steudtner of Germany drops in on a large wave at Praia do Norte in Nazare, Portugal, on November 1, 2015. The Praia do Norte beach has become a famous beach for big wave surfers around the world since Hawaiian surfer Garrett McNamara got a world record for the largest wave surfed in 2011.
Rafael Marchante / Reuters
Fernando Soberania uses a tool to scrape layers of gum from Seattle's famous "gum wall" at Pike Place Market on November 10, 2015. Tourists and locals have been sticking their used chewing gum on the walls of a section of Post Alley for the past 20 years, and although the walls will be cleaned down to bare brick, officials expect the gum-sticking tradition will quickly return.
Ted S. Warren / AP
Debris is pictured in Bento Rodigues district which was covered with mud after two dams owned by Vale SA and BHP Billiton Ltd burst, in Mariana, Brazil, November 10, 2015. The disaster left at least six dead and is still unfolding as the toxic mud reached the Atlantic ocean in late November.
Ricardo Moraes / Reuters
Spectators embrace each other as they stand on the playing field of the Stade de France stadium at the end of a friendly soccer match between France and Germany in Saint Denis, outside Paris, Friday, November 13, 2015. Hundreds made their way to the pitch after explosions were heard nearby. Multiple fatal attacks throughout the city prompted President Francois Hollande to announce he was closing the country's borders and declaring a state of emergency.
Christophe Ena / AP
A message that reads: "In the name of what?" and a rose is placed through a bullet hole in a window at the restaurant on Rue de Charonne, Paris, on November 15, 2015, where attacks took place on November 13. ISIS claimed responsibility for the attacks on a stadium, a concert hall and Paris cafes that left 130 people dead and over 350 wounded.
Frank Augstein / AP
People observe a minute of silence at the Trocadero in front the Eiffel Tower to pay tribute to the victims of the series of deadly attacks on Friday in Paris, France, on November 16, 2015.
Philippe Wojazer / Reuters
A Belgian soldier patrols a shopping street in central Brussels as police search the area during a continued high level of security following the recent deadly Paris attacks, on November 24, 2015.
Yves Herman / Reuters
A view of burned stumps as peatland forest is cleared by burning for a palm oil plantation at a company's grounds on November 1, 2015 in the outskirts of Palangkaraya, Central Kalimantan, Indonesia. The air pollution or haze has been an annual problem for the past 18 years in Indonesia. It's caused by the illegal burning of forest and peat fires on the islands of Sumatra and Borneo to clear new land for the production of pulp, paper and palm oil. Desperate civilians at the epicenter of Indonesia's haze crisis are taking the fight into their own hands, using whatever meager resources they have to confront the fires ravaging their communities as they tire of waiting for the government to take action. This disaster has been exacerbated by this year's long dry season, triggered by the El Nino weather phenomenon.
Ulet Ifansasti / Getty
Demonstrators confront police during a protest following the release of a video showing Chicago Police officer Jason Van Dyke shooting and killing Laquan McDonald on November 24, 2015 in Chicago, Illinois. Van Dyke was charged today with first degree murder for the October 20, 2014 shooting in which McDonald was hit with 16 bullets.
Scott Olson / Getty
Elin Harvey, 6, plays in snow for the first time near Norden, California, on December 5, 2015. An El Nino is forecasted for California, and regular precipitation has been welcomed after years of drought.
Max Whittaker / Reuters
Volunteers walk on a massive pile of lifejackets left behind by refugees and migrants who arrived on the Greek island of Lesbos after crossing the Aegean sea from Turkey on December 3, 2015.
Aris Messinis / AFP / Getty
Republican presidential candidate Donald Trump autographs a supporter's chest following his speech at a campaign rally at the Prince William County Fair Ground in Manassas, Virginia, on December 2, 2015.
Cliff Owen / AP
Gyrocopters fly over the capital of the United Arab Emirates, Dubai, during the World Air Games 2015, on December 9, 2015.
Karim Sahib / AFP / Getty
Police officers conduct a manhunt after a mass shooting in San Bernardino, California, on December 2, 2015. A married couple who have been identified as self-radicalized Islamic extremists opened fire on a holiday party at a social services agency in San Bernardino, killing 14 people and wounding 17 others, then fled the scene, triggering an intense manhunt and a shootout with police, where the couple was killed.
Mike Blake / Reuters
A so-called dirty thunderstorm with volcanic lightning, as Italy’s Mount Etna erupts on December 3, 2015.