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Summer Season Projected to Last Longer
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A new study by scientists at the State Key Laboratory of Tropical Oceanography, in China, and published in the journal Geophysical Research Letters, predicts that if emissions of greenhouse gases go john smith/AdobeStock.com unchecked, summers in the Northern Hemisphere could last nearly six months by 2100. The impacts will be felt on human health, agriculture and ecology, such as the timing of animal feeding, breeding and migration, as well as promoting more heat waves, droughts and wildfires.
The research analyzed six decades of historical daily climate records and employed climate models to project future trends. Summer was defined as the onset of temperatures in the hottest 25 percent of the year and winter as temperatures in the coldest 25 percent. The number of summer days in the Northern Hemisphere increased from 78 to 95 between 1952 and 2011.
Avian Assistants
Wild Birds Trained to Pick Up Litter
Crows, capable of complex thought and skilled problem solvers, can also make and use tools. Now, several projects aim to enlist crows and other wild creatures as volunteers to keep the environment tidy. A Dutch company, Crowded Cities, has a device called the CrowBar (Tinyurl.com/Crow BarInvention) that trains birds to collect discarded cigarette butts in exchange for food, creating a low-cost solution to a problem that is laborintensive for humans.
The machine presents a piece of food next to a cigarette butt on a platform, training the crow to expect food there. Then it starts dispensing the food only after the crow arrives, teaching the crow how the machine operates. Next, it presents only the cigarette butt, with no food. The crow starts looking around for the food and accidentally knocks the butt in, which releases a treat. The last step is to scatter a few cigarette butts on the ground around the CrowBar. When the training is complete, the crow will start collecting butts from the surrounding area and bringing them to the machine for a reward.
