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

Insurance and insurers are directly affected and concerned about climate fluctuations in the United States. Growing losses in the 1990s awakened many in the insurance business to the enormity of weather-related problems they faced and a need for better information about climate and its fluctuations including a new potential problem, climate change. This paper presents the views of experts from the crop insurance sector, the property-casualty insurance sector, and from the atmospheric sciences sector based on atmospheric research accomplished for the insurance industry for decades. The paper addresses how climatologists and insurers can and need to work together to effectively bring understanding and wise consideration of climate conditions and their future fluctuations and extremes to insurers. Considerable climatological analyses have been employed in the past by the crop insurance industry, but less by property insurers. Insurers can adjust to a change in climate but to do so will require clear evidence, which does not exist now for the United States, and an understanding as well as wide acceptance of the on-going change by regulators and the buying public. Atmospheric scientists can help insurers to mitigate weather losses, to assess risks, to measure critical perils, to educate about risks, and to learn about critical issues like climate change and long-range forecasts.

Interactions Between the Atmospheric Sciences and Insurers in the United States

Rainfall data from three summers were studied to discern possible urban and lake influences on precipitation processes and quantity over the Chicago region and southern Lake Michigan. The stabilizing influence of Lake Michigan on convective rainfall is considerable, with fewer raincells and lower rain rates than over adjacent rural areas. The lake effect is realized largely in less well-organized and weaker convective conditions, whereas squall lines do not exhibit any great diminishment in rainfall production over the lake. Average over-lake rainfall more than 40 km east of the western shore was reduced, estimated as being 36% less than the shoreline average. The urban influences on rain are most pronounced in well-organized convective systems, leading to localized increases in raincell initiations, mergers of raincells, and larger more intense raincells than occur over nearby rural areas. The net result is 15% more rain, on the average, over Chicago, and 10 to 20% more rain extending 40 km east over sou...

Urban and lake effects on summer rainfall in the chicago area

Throughout the 20th century scientists sought an explanation for the tall grass prairie in the central United States, a large area of tall grasses with a climate long believed better for forests th...

Climate Factors that Caused the Unique Tall Grass Prairie in the Central United States

Property insurance data available for 1949–2006 were assessed to get definitive measures of hurricane losses in the U.S. Catastrophes, events causing >$1 million in losses, were most frequent in the Southeast and South climate regions. Losses in these two regions totaled $127 billion, 85% of the nation’s total losses. During the period 1949–2006 there were 79 hurricane catastrophes, causing $150.6 billion in losses and averaging $2.6 billion per year. All aspects of these hurricanes showed increases in post-1990 years. Sizes of loss areas averaged one state in 1949–1967, but grew to 3 states during 1990–2006. Seven of the ten most damaging hurricanes came in 2004 (4) and 2005 (3). The number of hurricanes also peaked during 1984–2006, increasing from an annual average of 1.2 during 1949–1983 to 2.1 per year. Losses were $49.3 billion in 1991–2006, 32% of the 58-year total. Various reasons have been offered for such recent increases in hurricane losses including more hurricanes, more intense tropical storms, increased societal vulnerability in storm-prone areas, and a change in climate due to global warming, although this is debatable.

Characteristics of severe Atlantic hurricanes in the United States: 1949–2006

The temporal histories of 702 convective echoes measured in the St. Louis area during the 1973 summer were studied to discern potential effects on echo behavior of the urban influences and those effects resulting from the merger of two or more echoes. The 190 echoes that merged grew faster (50%), became taller (52%), and lasted longer (122%) than non-merger echoes. The average echo top growth 10 min after a merger was 1500 m, and on any given day 80% of the heights of merger echoes at a given stage of echo life were higher than those of non-merger echoes. The 137 echoes that crossed the urban area were longer lasting (119%), faster growing (61%), taller (30%), and more merged (44% vs 23%) than the non-urban echoes. The 61 urban echoes that subsequently merged over or beyond St. Louis were demonstrably longer lasting (110 vs 44 min) and taller (4800 m at 10 min after entry into the urban area and 5900 m at urban exit) than 76 urban echoes that did not merge. The urban echo that merged was also mea...

Stanley A. Changnon

Papers

Interactions Between the Atmospheric Sciences and Insurers in the United States

Urban and lake effects on summer rainfall in the chicago area

Climate Factors that Caused the Unique Tall Grass Prairie in the Central United States

Characteristics of severe Atlantic hurricanes in the United States: 1949–2006

Effects of Urban Areas and Echo Merging on Radar Echo Behavior