Moises Araya, 12, picks red ripe coffee beans at a plantation in San Miguel de Naranjo, 37 miles (60km) of San Jose, December 11, 2007. REUTERS/Juan Carlos Ulate By John McPhaul Reuters June 25, 2008 SAN JOSE, Costa Rica (Reuters) - Costa Rican coffee farmers are facing threats from climate change but the rising temperatures are also expanding high-altitude regions where the country's most prized beans are grown. Human emissions of greenhouse gases could cause the earth's surface temperature to rise anywhere between one and six degrees Celsius (1.8 and 10.8 degrees Fahrenheit) over the next 100 years, according to the United Nations, forcing growers of all crops to adapt to new weather conditions. In Costa Rica, the temperature increases may help transform mountainous land that was once too chilly for delicate coffee trees into prime coffee-planting territory. The strictly hard-bean Arabica coffee sought by specialty roasters is only found at high altitudes, so the shift could...