Causal attribution of recent biological trends to climate change is complicated because non-climatic influences dominate local, short-term biological changes. Any underlying signal from climate change is likely to be revealed by analyses that seek systematic trends across diverse species and geographic regions; however, debates within the Intergovernmental Panel on Climate Change (IPCC) reveal several definitions of a 'systematic trend'. Here, we explore these differences, apply diverse analyses to more than 1,700 species, and show that recent biological trends match climate change predictions. Global meta-analyses documented significant range shifts averaging 6.1 km per decade towards the poles (or metres per decade upward), and significant mean advancement of spring events by 2.3 days per decade. We define a diagnostic fingerprint of temporal and spatial 'sign-switching' responses uniquely predicted by twentieth century climate trends. Among appropriate long-term/large-scale/multi-species data sets, this diagnostic fingerprint was found for 279 species. This suite of analyses generates 'very high confidence' (as laid down by the IPCC) that climate change is already affecting living systems.

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A globally coherent fingerprint of climate change impacts across natural systems

There is now ample evidence of the ecological impacts of recent climate change, from polar terrestrial to tropical marine environments. The responses of both flora and fauna span an array of ecosystems and organizational hierarchies, from the species to the community levels. Despite continued uncertainty as to community and ecosystem trajectories under global change, our review exposes a coherent pattern of ecological change across systems. Although we are only at an early stage in the projected trends of global warming, ecological responses to recent climate change are already clearly visible.

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Ecological responses to recent climate change.

Drafting Authors: Neil Adger, Pramod Aggarwal, Shardul Agrawala, Joseph Alcamo, Abdelkader Allali, Oleg Anisimov, Nigel Arnell, Michel Boko, Osvaldo Canziani, Timothy Carter, Gino Casassa, Ulisses Confalonieri, Rex Victor Cruz, Edmundo de Alba Alcaraz, William Easterling, Christopher Field, Andreas Fischlin, Blair Fitzharris, Carlos Gay García, Clair Hanson, Hideo Harasawa, Kevin Hennessy, Saleemul Huq, Roger Jones, Lucka Kajfež Bogataj, David Karoly, Richard Klein, Zbigniew Kundzewicz, Murari Lal, Rodel Lasco, Geoff Love, Xianfu Lu, Graciela Magrín, Luis José Mata, Roger McLean, Bettina Menne, Guy Midgley, Nobuo Mimura, Monirul Qader Mirza, José Moreno, Linda Mortsch, Isabelle Niang-Diop, Robert Nicholls, Béla Nováky, Leonard Nurse, Anthony Nyong, Michael Oppenheimer, Jean Palutikof, Martin Parry, Anand Patwardhan, Patricia Romero Lankao, Cynthia Rosenzweig, Stephen Schneider, Serguei Semenov, Joel Smith, John Stone, Jean-Pascal van Ypersele, David Vaughan, Coleen Vogel, Thomas Wilbanks, Poh Poh Wong, Shaohong Wu, Gary Yohe

Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change

Ecological changes in the phenology and distribution of plants and animals are occurring in all well-studied marine, freshwater, and terrestrial groups These observed changes are heavily biased in the directions predicted from global warming and have been linked to local or regional climate change through correlations between climate and biological variation, field and laboratory experiments, and physiological research Range-restricted species, particularly polar and mountaintop species, show severe range contractions and have been the first groups in which entire species have gone extinct due to recent climate change Tropical coral reefs and amphibians have been most negatively affected Predator-prey and plant-insect interactions have been disrupted when interacting species have responded differently to warming Evolutionary adaptations to warmer conditions have occurred in the interiors of species’ ranges, and resource use and dispersal have evolved rapidly at expanding range margins Observed genetic shifts modulate local effects of climate change, but there is little evidence that they will mitigate negative effects at the species level

https://www.fws.gov/southwest/es/documents/R2ES/LitCited/LPC_2012/Parmesan_2006.pdf

Ecological and Evolutionary Responses to Recent Climate Change

The authors propose a new climatic drought index: the standardized precipitation evapotranspiration index (SPEI). The SPEI is based on precipitation and temperature data, and it has the advantage of combining multiscalar character with the capacity to include the effects of temperature variability on drought assessment. The procedure to calculate the index is detailed and involves a climatic water balance, the accumulation of deficit/surplus at different time scales, and adjustment to a log-logistic probability distribution. Mathematically, the SPEI is similar to the standardized precipitation index (SPI), but it includes the role of temperature. Because the SPEI is based on a water balance, it can be compared to the self-calibrated Palmer drought severity index (sc-PDSI). Time series of the three indices were compared for a set of observatories with different climate characteristics, located in different parts of the world. Under global warming conditions, only the sc-PDSI and SPEI identified an...

/pdf/a-multiscalar-drought-index-sensitive-to-global-warming-the-370wre0ti5.pdf

A Multiscalar Drought Index Sensitive to Global Warming: The Standardized Precipitation Evapotranspiration Index

The 1989 Illinois summertime cloud seeding results have been examined in the context of synoptic weather conditions. It was found that six of the 12 experimental units occurred under cold-front conditions, and four units under air-mass conditions when kinematic trigger was obvious. When cold fronts were present, the tallest daily echo tops, the highest first echoes, the strongest updrafts, and hail were observed. While deep convection occurred on both types of days, a larger amount of potential buoyancy was available and stronger vertical shear was present on cold-front days. Sixty echo cores treated near cloud top with silver iodide (Agl) or sand flares were examined before, at, and after treatment. It was expected that the cold-front cores would be larger than the air-mass cores. Instead, the air-mass cores in the mean were older, larger, more reflective, and contained more liquid water and a larger fraction of ice than the cold-front cores. The cold-front cores had a broad distribution in vertical motion as estimated by both aircraft and radar. This same broad distribution also was observed in the maximum values of height, area, and reflectivity. There were many small cold-front cores and a few large ones. The cold-front cores with the largest and strongest updrafts grew the tallest. This relationship was much weaker for the air-mass cores. It was postulated that the smaller cores were more subject to the detrimental effects of entrainment on cold-front days. On the air-mass days, all tracked cores were already joined with another echo by the time ot treatment. In this protected environment, less affected by vertical shear, even the smallest of the air-mass cores grew. Agl/sand differences also were examined. For the cold-front cores, it was found that at treatment time, there was a disproportionate number of small Agl-treated cores, and the largest cores were treated with sand flares. The sand cores also had the largest pre-treatment and treatment time growth rates. No seeding effect could be deduced from the cold front sample because of this bias towards smaller Agl-treated cores. No such bias was observed for the air-mass cores. However, the air-mass sand-treated cores grew taller than the Agl-treated cores. Since cloud seeding was expected to lead to an increase in vertical growth, if seeding affected the growth of the individually treated cores, it was in a negative way for this small sub-sample of air-mass cores. However, in terms of core duration, maximum horizontal area and maximum reflectivity, the sand- and Agl-treated cores were similar. These data failed to confirm the earliest steps of the dynamic seeding hypothesis suggesting that silver iodide treatment invigorates individual cloud growth.

Results of the 1989 Exploratory Cloud Seeding Experiment in Illinois Based on Synoptic Weather Conditions

Comments on “The Effect on Rainfall of a Large Steelworks”

Data recorded over a 10-year period from a network of 11 recording rain gages was used in a study of the distribution characteristics of excessive rainfall amounts over the 10-square-mile urban area of Champaign-Urbana, Illinois. All storms were used in which one or more rain gages recorded an amount equalling or exceeding the 2-year return period value of point rainfall for durations of 30 minutes, 1 hour, 2 hours, 3 hours, 6 hours, 12 hours, and 24 hours.

Factors investigated include: the frequency of excessive rainfall amounts within the area compared with the frequency at a given observation point within the area; the percentage of the urban area experiencing excessive rainfall amounts during individual storms and the frequency distribution of this percentage; the adequacy of a single point to define the frequency distribution of areal mean rainfall within a small area; the frequency with which excessive amounts for 30-minute to 24-hour periods occur within the same storms; and urban influences on the distribution of heavy storm rainfall.

Based on the 10-year sampling period, results indicate that twice as many excessive rainfall amounts occur within a 10-square-mile area compared with the number recorded at specific points; on the average, the percentage of the 10-square-mile area experiencing excessive rainfall amounts increases with increasing storm duration; the majority of the excessive amounts for duration of 30 minutes to 24 hours occur in the same storms; a point rainfall record is a satisfactory index of the areal mean rainfall frequency distribution in a 10-square-mile area; and urban influences, if present, are not of practical significance.

Distribution of Excessive Rainfall Amounts over an Urban Area

Climate was the most important factor in producing the Great Lakes we have today Through glacial action during the Pleistocene Epoch, the surface topography, shape, and depth of Lake Michigan were determined Today the Lake Michigan region has a humid, continental climate Summers are hot and humid, and winters are cold and stormy Lake Michigan, as a reservoir for storing and exchanging heat, is a moderating influence on extreme temperatures The Lake is also a moisture source, especially during late fall and early winter when Arctic air flows over the still-warm lake Heavy snows in the lee of the Lake can result Regional atmospheric dispersion conditions are generally good in locations away from the Lake Air mass stagnation conditions are expected only four times a year, and three of these should last no longer than two days each However, over and near the Lake, conditions can be extremely different During the warm season, when the air over the Lake is relatively cold and stable, onshore airflow can produce a number of conditions leading to high pollutant concentrations within 10 km of the Lake shore The pollutants also have effects on the weather, including reduced visibility and solar radiation, and increasedmore » cloudiness They may also play a role in producing excess precipitation downwind of large industrial and population centers Atmospheric pollution also provides an important pathway for the transfer of pollutants deposited on the Lake surface both by dry fallout and in precipitation« less

Environmental status of the Lake Michigan region. Volume 8. Atmospheric environment of the Lake Michigan drainage basin

AMERICAN METEOROLOGICAL SOCIETY | 915 Applied climatology has been the foundation upon which the world’s weather-sensitive activities and infrastructure have been developed. Applications of climate data and information have likely contributed more to the development of most nations than any other function of the atmospheric sciences. Th e recent development of useful weather forecasts has been important, but these developments have not overshadowed a parallel recent progress in applied climatology. A variety of scientifi c and technological advances, coupled with a changing society, have led applied climatology into its golden era. What is applied climatology? The answer may seem obvious, but the defi nition of applied climatology is elusive for several reasons. Activities falling under the umbrella of applied climatology are spread among many disciplines, as well as having interfaces with many parts of the atmospheric sciences, collectively forming myriad interactions. Th e fi eld is truly interdisciplinary, embracing climatologists and those of other disciplines, including hydrology, agriculture, engineering, and business. Fift y years ago, leaders in the fi eld defi ned applied climatology as the scientifi c analysis of climate data in light of a useful application for an operational purpose. My interpretation is that applied climatology describes, defi nes, interprets, and explains the relationships between climate conditions and countless weather-sensitive activities. For example, if viewed in a business sense, applied climatology would embrace interactions with marketing, sales, customer services, research support, and the delivery arm for climatological data and information. Th e

Stanley A. Changnon

Papers

Results of the 1989 Exploratory Cloud Seeding Experiment in Illinois Based on Synoptic Weather Conditions

Comments on “The Effect on Rainfall of a Large Steelworks”

Distribution of Excessive Rainfall Amounts over an Urban Area

Environmental status of the Lake Michigan region. Volume 8. Atmospheric environment of the Lake Michigan drainage basin

Applied Climatology: The Golden Age Has Begun