Earth’s climate is changing rapidly.
No, it is not a hoax, not a projection for the future, not a scare tactic from whatever political or advocacy group that you or your favorite politician may not like. In our lifetimes, it has changed–generally growing warmer and often dryer, with daily weather more prone to extremes–winds, rain, snow, cold, heat, more destructive storms leading to more extensive flooding, wildfires, economic damage, deaths, etc.
The research predicting and showing climate change has been there since at least the 1970’s. Our children, our children’s children, future society will pay an even greater price than we are paying today.
One of many immediate consequences of a changing climate has been and is a noticeable loss of biodiversity–the extinction and disappearance of animal and plant species.
Could human beings eventually face this threat as well? We have seen great and even abrupt shifts of Earth’s climate in the past but, until the present day, we have not seen it during a time when human beings were the dominant species.
For more, see —
The sixth mass extinction on Earth
Further loss of plant and animal species due to climate change may occur abruptly
Additional research:
*Adams, A. M., Trujillo, L. A., Campbell, C. J., Akre, K. L., Joaquin Arroyo‐Cabrales, Burns, L., Coleman, J. T. H., Dixon, R. D., Francis, C. M., Melquisedec Gamba‐Rios, Kuczynska, V., McIntire, A., Medellín, R.,A., Morris, K. M., Ortega, J., Reichard, J. D., Reichert, B., Segers, J. L., Whitby, M. D., & Frick, W. F. (2024). The state of the bats in North America. Annals of the New York Academy of Sciences, 1541(1), 115-128. [PDF] [Cited by]
“The world’s rich diversity of bats supports healthy ecosystems and important ecosystem services. Maintaining healthy biological systems requires prompt identification of threats to biodiversity and immediate action to protect species, which for wide-ranging bat species that span geopolitical boundaries warrants international coordination. Anthropogenic forces drive the threats to bats throughout North America and the world. We conducted an international expert elicitation to assess the status of 153 bat species in Canada, the United States, and Mexico. We used expert assessment to determine the conservation status, highest impact threats, and recent population trends for these species. We found that 53% of North American bat species have moderate to very high risk of extinction in the next 15 years. The highest impact threats varied with species and country, and four IUCN threat categories had the greatest overall impacts: Climate Change, Problematic Species (including disease), Agriculture, and Energy Production. Experts estimated that 90% of species assessed had decreasing population trends over the past 15 years, demonstrating the need for conservation action. Although the state of North American bats is concerning, we identify threats that can be addressed through internationally collaborative, proactive, and protective actions to support the recovery and resilience of North American bat species.”
*James, D. G. (2024). Monarch Butterflies in Western North America: A Holistic Review of Population Trends, Ecology, Stressors, Resilience and Adaptation. Insects, 15(1), 40. [PDF] [Cited by]
“Monarch butterfly populations in western North America suffered a substantial decline, from millions of butterflies overwintering in California in the 1980s to less than 400,000 at the beginning of the 21st century. The introduction of neonicotinoid insecticides in the mid–1990s and their subsequent widespread use appears to be the most likely major factor behind this sudden decline. Habitat loss and unfavorable climates (high temperatures, aridity, and winter storms) have also played important and ongoing roles. These factors kept overwintering populations stable but below 300,000 during 2001–2017. Late winter storm mortality and consequent poor spring reproduction drove winter populations to less than 30,000 butterflies during 2018–2019. Record high temperatures in California during the fall of 2020 appeared to prematurely terminate monarch migration, resulting in the lowest overwintering population (1899) ever recorded. Many migrants formed winter-breeding populations in urban areas. Normal seasonal temperatures in the autumns of 2021 and 2022 enabled overwintering populations to return to around the 300,000 level, characteristic of the previous two decades. Natural enemies (predators, parasitoids, parasites, and pathogens) may be important regional or local drivers at times but they are a consistent and fundamental part of monarch ecology. Human interference (capture, rearing) likely has the least impact on monarch populations. The rearing of monarch caterpillars, particularly by children, is an important human link to nature that has positive ramifications for insect conservation beyond monarch butterflies and should be encouraged.”
*Young, D. J. N., Slaton, M. R., & Koltunov, A. (2023). Temperature is positively associated with tree mortality in California subalpine forests containing whitebark pine. Ecosphere, 14(2), e4400. [PDF] [Cited by]
“Whitebark pine (Pinus albicaulis Engelm.) is a keystone high-elevation tree species occurring across much of western North America, yet it has been listed as threatened under the US Endangered Species Act due to rapid population declines and extensive ongoing pressures from white pine blister rust (Cronartium ribicola), mountain pine beetle (Dendroctonus ponderosae), and increasing temperature and aridity associated with climate change. Past research has shown that whitebark pine mortality is more likely in hotter and drier sites, but no broad-extent analyses spanning multiple ecoregions have directly quantified the relationship between mortality probability and its environmental drivers at a fine spatial scale. To address this gap, we used spatially continuous high-resolution (30 m) maps of mortality in California produced by a remote sensing-based change detection algorithm, and we developed generalized additive models to explain this mortality variability using relevant biophysical variables. We found that maximum daily temperature was strongly positively associated with mortality intensity and that mortality was also generally more intense in sites with greater solar exposure (e.g., south-facing slopes). Our results support the interpretation that as climate warms and aridity increases, populations in “trailing edge” (i.e., hot, dry) sites are most vulnerable. The environmental relationships we quantify will aid in identifying the locations and environments with the greatest risk of future mortality as well as those likely to serve as refugia.”
Questions? Please let me know (engelk@grinnell.edu).
