Week in pictures: 30 August - 5 September 2014

image copyright Justin Sullivan/Getty Images
image captionHouseboats are dwarfed by the steep banks of Shasta Lake at Bridge Bay Resort in Redding, California, which is currently near just 30% of its total capacity. This is the lowest it has been since 1977. The state has been hit by its worst drought in a century, leaving hundreds of households and landowners without water.
image copyrightYoussef Boudlal/reuters
image captionA mother says goodbye to her son, a volunteer in the Kurdish Peshmerga forces, as he prepares to leave home for the front line in the battle with Islamic State militants, near Tuz Khurmatu, north-east of Tikrit, Iraq.
image copyrightPatrick Semansky/ap
image captionMembers of the Cincinnati Reds watch from the dugout as heavy rain falls during the first inning of an inter-league baseball game against the Baltimore Orioles, in Baltimore.
image copyrightHOW HWEE YOUNG/epa
image captionChinese dancer and choreographer Yang Liping is seen during a performance of The Peacock in Beijing, China. Yang Liping is one of China's most prolific dancers, made famous by her creation and performance Spirit of Peacock in 1986, which won numerous awards and was performed in the closing of the 1990 Asian Games.
image copyrightANTHONY ANEX/epa
image captionA flock of alpine sheep make their way along a high altitude mountain path as they head from the summer grazing high above the Aletschgletscher glacier down to Belalp in the canton of Valais, during the Schaeferwochenende (Sheep weekend) in Switzerland.
image copyrightJim Urquhart/reuters
image captionThe art installation Pulse and Bloom is seen at the Burning Man arts and music festival in the Black Rock Desert of Nevada in the US. More than 65,000 people spent a week in the remote desert, cut off from much of the outside world, to experience art, music and the unique community that develops.
image copyrightLEON NEAL/AFP
image captionBritish Prime Minister David Cameron greets German Chancellor Angela Merkel during the 2014 Nato summit in Newport, Wales. On the opening day, Western leaders criticised Russia for its "destabilising" influence on the crisis in eastern Ukraine.
image copyrightCARLOS CAMPANA/AFP
image captionSeismologists in Ecuador said the Tungurahua volcano is showing increased activity. About 40 explosions were registered on Monday and even though their intensity diminished, experts have not ruled out a renewed sudden increase. Tungurahua, which had been dormant since 1999, lies 135km (85 miles) south-east of the Ecuadorean capital, Quito.
image copyrightWong Maye-E/ap
image captionNorth Koreans enjoy a ride at the Kaeson Youth Amusement Park in Pyongyang.
image copyrightJoe Giddens/PA
image captionCompetitors take part in the Spartan Sprint event at Pippingford Park in East Sussex, England. Spartan Sprint is a muddy 5km (3-mile) cross-country course, which includes ropes, monkey bars, crawls under barbed wire and a fire leap across flaming logs.
image copyrightJOE KLAMAR/AFP
image captionSlovakia's High Tatras mountains are seen from the solar observatory station on the Lomnicky Stit peak. The coronal station at the observatory sits at more than 2,600m above sea level and was built between 1957 and 1962.