Water shortages, sudden floods on the climate change menu in South America
Researchers already know that the world’s tropical glaciers are melting fast, but a new study published in The Cryosphere, an European Geosciences Union journal, helps pinpoint some of the potential impacts. The research focused on the Bolivian Andes, where glaciers dwindled by 43 percent in the last 30 years. The melting ice has created lakes that could burst and flood downstream towns, according to lead author Simon Cook a lecturer at the Manchester Metropolitan University in the UK.
The glacier meltdown also threatens regional water supplies. The 2.3 million residents of La Paz and El Alto get about 15 percent of their water supply from glaciers, and double that during the dry season. One lake in the region has already dried up, according to the authors, who said their study is one of the first to look specifically at recent large-scale glacier change in Bolivia. Continue reading “Melting Andes glaciers pose risk in Bolivia”→
Global temperatures stayed near record-high levels in Autumn, with last month ending up as the second-warmest September on record, going back to 1880. For the month, the average sea- and land-surface temperature was 1.60 degrees Fahrenheit above the 20th century average, just 0.07 degrees Fahrenheit cooler than September 2015, according to the latest monthly State of the Climate report from NOAA’s National Centers for Environmental Information.
Long-term studies show potential impacts of climate change
A new set of scientific reports highlights the value of long-term observations in relatively undisturbed ecosystems and also offers a preview of how global warming may change Antarctica in coming decades.
The research shows that a period of unusual warmth in 2001 and 2002, caused by a confluence two natural climate cycles, accelerated the microbial food chain and shook up the distribution of penguin populations and thinned glaciers according to October issue of the journal BioScience .
The research came out of two long-term ecological research stations, including Palmer Station, on the West Antarctic Peninsula, where scientists study how “changing sea ice extent influences marine ecology and the multilayered food webs of the coastal, nearshore, and continental slope ecosystems.” Other studies were done at the McMurdo Dry Valleys LTER, in an ice-free polar desert where glacial meltwater plays a huge role in ecosystems. Continue reading “How will Antarctica respond to global warming?”→
Heat-trapping greenhouse gases may dessicate Colorado River Basin
It’s very likely the southwestern U.S. will be hit by droughts unlike any seen since the region was settled by Europeans. Global warming has driven the odds of a 10-year drought to at least 50 percent, and the chances of a 35-year megadrought range from 20 to 50 percent during the next century, according to a new study led by researchers with Cornell, the University of Arizona and the U.S. Geological Survey.
A slowdown of a key heat-carrying Atlantic current may not be due to melting Arctic ice, but to changes in the Southern Hemisphere, according to University of Washington scientists studying how climate change may affect global wind and ocean flows.
Their new study, published in the journal Geophysical Research Letters, analyzed data from satellites and ocean sensors off Miami that have tracked the Atlantic overturning circulation for more than a decade. Together they show a definite slowdown since 2004, confirming a trend suspected before then from spottier data.
The Paris climate agreement has reached the milestones needed to take effect, as 70 countries, representing almost 57 percent of global emissions, have formally signed on to the deal. According to the United Nations, Canada, the European and Nepal deposited their instruments of ratification with the global body Wednesday, Oct. 6. The agreement, aimed at limiting global warming to 1.5 degrees Celsius above the pre-industrial level, will become effective Nov. 4.
In a prepared statement, UN Secretary General Ban Ki-moon said, “Global momentum for the Paris Agreement to enter into force in 2016 has been remarkable. What once seemed unthinkable is now unstoppable. ”
Under the agreement, more than 190 countries agreed late last year to try and decarbonize the world’s energy systems by the middle of the century to end the buildup of heat-trapping pollution that has already raised the world’s average temperature by about 1 degree Celsius since 1850. In the past few months, the global temperature has spiked near the 1.5 degree threshold. Climate scientists agree that capping the rise at 2 degrees is critical to avoiding catastrophic climate change impacts like deadly droughts and heatwaves, floods and other extreme weather events.
The treaty also requires richer countries to set up a mitigation fund to help developing countries adapt to impacts. All countries party to the deal must submit individual plans and update them on a regular basis.
Commenting on the news from the Rose Garden, President Barack Obama said that, if the world follows through on the deal’s terms, “history may well judge it as a turning point for our planet.” More from the White House here.
Thank you to every nation that moved to bring the Paris Agreement into force. History will judge today as a turning point for our planet.
Making it real will require a massive transformation of the world’s economy, and despite the good intentions, there are not many strong signs that will actually happen soon enough. Some recent studies have also warned that the planet is just 15 years away from hitting the 1.5 degree threshold, and that without immediate and massive greenhouse gas cuts, the 2-degree Celsius mark will be passed as early as 2050.
Understanding the urgency, the world community may try to ramp up climate action as soon as the COP22 climate conference in Marrakesh in November.
Australian scientists document early start to melt season
Australian scientists say Antarctic sea ice started its annual spring retreat early this year and has set new daily record lows for extent during late September — during the Austral spring, when Antarctic sea ice is at a maximum.
In a press release, the Antarctic Climate & Ecosystems Cooperative Research Centre said the sea ice extent started its annual retreat early, just two years after winter sea ice extent around Antarctica reached a new record high in September 2014, when it exceeded 20 million square kilometres for the first time since satellite measurements began in 1979.
This year, Antarctic sea ice began its annual spring retreat about four weeks earlier than average, after peaking at 18.5 million square kilometres on 28 August 2016, which was close to the lowest winter maximum on record.