CHEMISTRY YEAR
IN
REVIEW
HEADLINES
NEWSCOM
CLIMATE CHANGE
Nobel Prizes At A Glance Here are the scientists who got the coveted phone call from Sweden this year CHEMISTRY
Climate Pact Clinched As CO2 levels pass 400-ppm mark, countries hammered out new accord in Paris Tomas Lindahl Francis Crick Institute
Paul Modrich Duke University School Of Medicine
Global average carbon dioxide levels in the atmosphere inched past 400 ppm in early 2015. That and other scientific information turned up the heat on governments for collective action to fend off anthropogenic climate change. To that end, United Nations talks culminated earlier this month in a new global agreement intended to slow and eventually ramp down societies’ greenhouse gas emissions. The global average atmospheric concentration of CO2 surpassed 400 ppm in March, according to the National Oceanic & Atmospheric Administration’s Global Greenhouse Gas Reference Network. Scientists estimate that atmospheric levels of CO2 haven’t been that high since a warm period some 4.5 million years ago. Meanwhile, governments drew up a new global agreement on climate change that involves emission controls by all countries. As part of that deal, reached in Paris on Dec. 12, 185 nations and the European Union each made a pledge individually on how they will put the brakes on their greenhouse gas emissions. If countries keep those promises, global average temperatures are estimated to climb to nearly 3 °C above preindustrial levels by 2100, according to several analyses. The final pact aims to hold global average temperatures to “well below” a 2 °C rise by 2100. It also includes a call “to pursue” efforts that might limit the rise to 1.5 °C. That more ambitious target was sought by low-lying island nations that likely would be inundated by sea-level rise due to warming and poor African countries projected to experience more intense droughts and flooding due to climate change. To get to the 2 °C target the agreement calls for countries to revisit their emission-control pledges every five years. The hope is for governments to scale up those promises by curtailing emissions even more over time as technology for renewable energies and carbon capture and sequestration improves and becomes cheaper. The pact also calls for governments to provide international funding to help developing countries reduce emissions and adapt to the impacts of climate change.—CHERYL HOGUE
Aziz Sancar University of North Carolina, Chapel Hil
PHYSIOLOGY/MEDICINE For developing drugs (ivermectin, avermectin, and artemisinin) that cure parasite-induced diseases such as river blindness and malaria
William Campbell Drew University
¯ mura Satoshi O Kitasato University
Youyou Tu China Academy of Traditional Chinese Medicine
Takaaki Kajita University of Tokyo
Arthur McDonald Queen’s University, Ontario
PHYSICS For showing that neutrinos oscillate among three different forms, a phenomenon that proves the subatomic particles have mass
CEN.ACS.ORG
30
DECEMBER 21, 2015
AP (LINDAHL), KEVIN WOLF/AP IMAGES FOR HHMI (MODRICH), NEWSCOM (CAMPBELL , KAJITA, OMURA, TU), MAX ENGLUND/UNC HEALTH CARE (SANCAR), QUEEN’S U (MCDONALD)
For determining the detailed mechanisms of three types of DNA repair, processes that maintain life’s genetic blueprint
