July 2017 was statistically tied with July 2016 as the warmest July in the 137 years of modern record-keeping, according to a monthly analysis of global temperatures by scientists at NASA‘s Goddard Institute for Space Studies (GISS) in New York.
Last month was about 0.83 degrees Celsius warmer than the mean July temperature of the 1951-1980 period. Only July 2016 showed a similarly high temperature (0.82 °C), all previous months of July were more than a tenth of a degree cooler.
Starting with this update, the previously used ocean data set ERSST v4 was replaced by the newer ERSST v5. This contributed to the changes of some of the data in last month’s update. For more information, see the Updates to Analysis and the History Pages.
A global map of the June 2017 LOTI (land-ocean temperature index) anomaly, relative to the 1951-1980 June average. View larger image.
The monthly analysis by the GISS team is assembled from publicly available data acquired by about 6,300 meteorological stations around the world, ship- and buoy-based instruments measuring sea surface temperature, and Antarctic research stations.
The modern global temperature record begins around 1880 because previous observations didn’t cover enough of the planet. Monthly analyses are sometimes updated when additional data becomes available, and the results are subject to change.
New study shows that the large-scale difference between a warm Atlantic and relatively cold Pacific ocean temperatures plays a fundamental role in causing droughts, and enhancing wildfire risks in California and the southwest.
the Atlantic/Pacific temperature difference shows pronounced variations on timescales of more than 5 years. Like swings of a very slow pendulum, this implies that there is predictability in the large-scale atmosphere/ocean system, which we expect will have a substantial societal benefit.
A new study shows that difference in water temperature between the Pacific and the Atlantic oceans together with global warming impact the risk of drought and wildfire in southwestern North America.
…”we were able to show that without anthropogenic effects, the droughts in the southwestern United States would have been less severe.”
..The new findings show that a warm Atlantic and a relatively cold Pacific enhance the risk for drought and wildfire in the southwestern US. “According to our study, the Atlantic/Pacific temperature difference shows pronounced variations on timescales of more than 5 years. Like swings of a very slow pendulum, this implies that there is predictability in the large-scale atmosphere/ocean system, which we expect will have a substantial societal benefit,”…
…”we can use our climate computer model to determine whether on average the next year will have drier or wetter soils or more or less wildfires. Our yearly forecasts are far better than chance.”…
Yoshimitsu Chikamoto, Axel Timmermann, Matthew J. Widlansky, Magdalena A. Balmaseda, Lowell Stott. Multi-year predictability of climate, drought, and wildfire in southwestern North America. Scientific Reports, 2017; 7 (1) DOI: 10.1038/s41598-017-06869-7
researchers found no correlation with summer temperatures but a clear one for winter — the coldest winters were associated with the smallest beaks, whereas warmer winters were associated with larger beaks.
…in the 1990s, researchers began to explore a new question concerning the relationship between climate and the evolution of beak size…..[before this study]… feeding habits were believed to be the greatest driving force in beak evolution…
…[comparing] differences between individuals of the same species that are living in wildly different conditions…. the researchers found no correlation with summer temperatures but a clear one for winter — the coldest winters were associated with the smallest beaks, whereas warmer winters were associated with larger beaks.
…Allen’s Rule, which states that warm-blooded animals living in cold climates will have shorter limbs and appendages than those that live in warmer climates. The biological mechanism behind this rule is thermoregulation — more body surface area helps animals to shed heat better whereas less surface area helps them to conserve it. Since a bird’s beak plays a large role in thermoregulation — it has lots of blood vessels and is not covered in feathers — researchers wondered whether hotter climates beget larger beaks and colder climates beget smaller ones. Indeed, studies revealed that climate has influenced beak size, but not which type of climate had more of an overall impact….
Nicholas R. Friedman, Lenka Harmáčková, Evan P. Economo, Vladimír Remeš. Smaller beaks for colder winters: Thermoregulation drives beak size evolution in Australasian songbirds. Evolution, 2017; DOI: 10.1111/evo.13274
Seventy-four percent of the world’s population will be exposed to deadly heatwaves by 2100 if carbon gas emissions continue to rise at current rates, according to a new study. Even if emissions are aggressively reduced, the percent of the world’s human population affected is expected to reach 48 percent.
“We are running out of choices for the future,” said Camilo Mora, associate professor of Geography in the College of Social Sciences at the University of Hawaii at Manoa and lead author of the study. “For heatwaves, our options are now between bad or terrible. ….. The human body can only function within a narrow range of core body temperatures around 37oC. Heatwaves pose a considerable risk to human life because hot weather, aggravated with high humidity, can raise body temperature, leading to life threatening conditions.”
…For example, by 2100 New York is projected to have around 50 days with temperatures and humidities exceeding the threshold in which people have previously died. That same year, the number of deadly days for Sydney will be 20, 30 for Los Angeles, and the entire summer for Orlando and Houston….
Camilo Mora, Bénédicte Dousset, Iain R. Caldwell, Farrah E. Powell, Rollan C. Geronimo, Coral R. Bielecki, Chelsie W. W. Counsell, Bonnie S. Dietrich, Emily T. Johnston, Leo V. Louis, Matthew P. Lucas, Marie M. McKenzie, Alessandra G. Shea, Han Tseng, Thomas W. Giambelluca, Lisa R. Leon, Ed Hawkins, Clay Trauernicht. Global risk of deadly heat. Nature Climate Change, 2017; DOI: 10.1038/NCLIMATE3322
…They found that when mean summer temperatures in the South Asia nation went from 27 to 27.5 degrees Celsius, the probability of a heat wave killing more than 100 people grew from 13 percent to 32 percent — an increase of 146 percent….
Omid Mazdiyasni et al. Increasing probability of mortality during Indian heat waves. Science Advances, June 2017 DOI: 10.1126/sciadv.1700066
Most bird chicks need parental care to survive. In biparental species the chicks have greater chances of success if both parents participate in this task, especially under hostile situations. An international team of scientists has revealed that when temperatures rise, males and females in pairs of plovers shift incubation more frequently….The paper…analysed the behaviour of 36 populations of 12 plover species. Its results reveal that male plovers assist the females during daytime incubation. “Males’ participation in daytime incubation increases both with ambient temperature and with as the variability of maximum temperatures during the incubation period,” the expert stresses. The research demonstrates that a rise in temperature changes these bird pairs’ behaviour and their daily routine in terms of nest attendance….The conclusion of this new paper is that climate variations strongly influence parental cooperation.
Orsolya Vincze, András Kosztolányi, Zoltán Barta, Clemens Küpper, Monif Alrashidi, Juan A. Amat, Araceli Argüelles Ticó, Fiona Burns, John Cavitt, Warren C. Conway, Medardo Cruz-López, Atahualpa Eduardo Desucre-Medrano, Natalie dos Remedios, Jordi Figuerola, Daniel Galindo-Espinosa, Gabriel E. García-Peña, Salvador Gómez Del Angel, Cheri Gratto-Trevor, Paul Jönsson, Penn Lloyd, Tomás Montalvo, Jorge Enrique Parra, Raya Pruner, Pinjia Que, Yang Liu, Sarah T. Saalfeld, Rainer Schulz, Lorenzo Serra, James J. H. St Clair, Lynne E. Stenzel, Michael A. Weston, Maï Yasué, Sama Zefania, Tamás Székely. Parental cooperation in a changing climate: fluctuating environments predict shifts in care division. Global Ecology and Biogeography, 2017; 26 (3): 347 DOI: 10.1111/geb.12540
By Jeannette E. Warnert April 5, 2017 University of California Division of Agriculture and Natural Resources Blog
The new publication, Adapting Forests to Climate Change, can be downloaded free from the UC ANR Catalog. It is the 25th in the Forest Stewardship series, developed to help forest landowners in California learn how to manage their land. It was written by Adrienne Marshall, a doctoral student at the University of Idaho; Susie Kocher, UC Cooperative Extension forestry and natural resources advisor; Amber Kerr, postdoctoral scholar with the UC John Muir Institute of the Environment; and Peter Stine, U.S. Forest Service.
The document provides specific recommendations for care of three common types of forest in California: mixed conifer, oak woodland and coastal redwood forests… see page 12 for specific management recommendations.
…Scientists and land managers are heading into the mountains to measure the greenhouse gas activity at 16 hand-picked meadows—some recently restored, others degraded from a century of grazing and logging.
The four-year study is part of California’s pioneering effort to reduce carbon emissions. The project is designed to determine whether restored meadows hold more carbon than those that have been degraded. The outcome could prove pivotal for California and the planet. Worldwide, soils store three times more carbon than vegetation and the atmosphere combined. If the research shows restored meadows improve carbon storage, it could stimulate meadow restoration around the world….
…A December study published in Nature… found rising temperatures are stimulating a net loss of soil carbon to the atmosphere. Warmer soils accelerate the flux, sending more carbon into the ground and more carbon dioxide back out into the atmosphere. As warmth increases microbial activity, decomposition and respiration outpace photosynthesis, particularly in the world’s colder places. …” The changes could drive a carbon–climate feedback loop that could accelerate climate change.”…
…The research covers meadows from the base of Lassen Peak in the north to areas nearer to Los Angeles. The meadows range in elevation from 3,045 to nearly 8,700 feet; they include granitic, volcanic and metamorphic soils. A critical facet of the partnership is developing precise procedures for when and how to measure and analyze meadow greenhouse gases.
……a limited study conducted by the University of Nevada, Reno (U.N.R.). Scientists collected soil samples at seven meadows in the northern Sierra restored between 2001 and 2016, pairing restored sites with similar, adjacent unrestored sites….found an average of 20 percent more soil carbon in restored meadows, with one site recording an increase of over 80 percent. Meadows immediately begin storing carbon following restoration, with significant increases over 15 years, says Cody Reed, a research assistant working with Ben Sullivan, a U.N.R. soil scientist and assistant professor. The investigation seems to show restored meadows add soil carbon and also slow losses to the atmosphere.
…[In another study] they found surprised them: Carbon dioxide emissions were unaffected by soil moisture content, and methane sequestration was prevalent, particularly on the dry side of wet meadow. The 2014 study also found plant species richness and soil carbon concentration appeared more important than soil moisture in explaining carbon fluxes.
May 11, 2017 National Center for Atmospheric Research/University Corporation for Atmospheric Research (from ScienceDaily)
…The study paints a detailed picture of how temperature has affected the runoff ratio — the amount of snow and rain that actually makes it into the river — over time, and the findings could help improve water supply forecasts for the Rio Grande, which is a source of water for an estimated 5 million people. The study results also suggest that runoff ratios in the Upper Rio Grande and other neighboring snow-fed watersheds, such as the Colorado River Basin, could decline further as the climate continues to warm.
“The most important variable for predicting streamflow is how much it has rained or snowed,” said NCAR scientist Flavio Lehner, lead author of the study. “But when we looked back hundreds of years, we found that temperature has also had an important influence — which is not currently factored into water supply forecasts. We believe that incorporating temperature in future forecasts will increase their accuracy, not only in general but also in the face of climate change….
Current operational streamflow forecasts depend on estimates of the amount of snow and rain that have fallen in the basin, and they assume that a particular amount of precipitation and snowpack will always yield a particular amount of streamflow.
In recent years, those forecasts have tended to over-predict how much water will be available, leading to over-allocation of the river…”The effect of temperature on runoff ratio is relatively small compared to precipitation,” Lehner said. “But because its greatest impact is when conditions are dry, a warmer year can make an already bad situation much worse.”…
Climate scientists have shown the early mitigation needed to limit eventual warming below potentially dangerous levels has a climate ‘payback’ much earlier than previously thought.
…Ciavarella and the team discovered that it takes less than 20 years in many regions for the risk of extreme seasonal temperatures (one-in-ten-year extreme heat events) to halve following the start of aggressive emissions reductions.
Andrew Ciavarella added: “We show that the global exposure to climate risk is reduced markedly and rapidly with substantial reductions of greenhouse gas emissions. It had been thought previously that most of the benefits of mitigation would have been hidden by natural climate variability until later in the century.”…
Andrew Ciavarella, Peter Stott, Jason Lowe. Early benefits of mitigation in risk of regional climate extremes. Nature Climate Change, 2017; DOI: 10.1038/nclimate3259