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10 Posts tagged with the climate_change tag
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Climate Confusion: Lessons and Pitfalls in the study of Climates Past

 

Professor John Lowe – Royal Holloway, University of London

 

Earth Sciences Seminar Room, (Basement, WEB 05, Mineralogy Seminar Room)

 

9th December - 4.00 pm

 

Accurate reconstruction of the timing and pattern of past climate variations is pivotal to a wide range of scientific studies.  Climate modellers may use the results to test the functioning and/or predictive capabilities of numerical climate simulations.  Earth scientists use them to assess the role of climate forcing on a range of earth surface processes, operating over very different timescales. Archaeologists have long considered the possible influence of climate on human evolution and dispersal.  Part of the remit of environmental science is to understand how climatic factors regulate processes of major societal significance, such as groundwater recharge, aridification and flood recurrence. 

 

These various studies all depend upon the availability of reliable climatic histories, and an understanding of how the global climate system works.  However, recent discoveries are increasingly pointing to a serious and pervasive problem in this regard, especially with regard to how we measure the global environmental response to abrupt climatic events (those that take place in less than one hundred years). 

 

In this talk I will endeavour to address, and to stimulate debate about, three things: (a) the nature of the problem, by referring to recent advances in our understanding of the history of global climate variability during the late Quaternary (the last c.150,000 years or so); (b) the promise that new approaches in geological dating offer for delivering more precise chronologies of past climatic variation;  and (c) the challenges that lie ahead, and that need to be met, before the stamp of climate change on the geo-archaeological record can be appraised with more assurance.

 

More information on attending seminars at http://www.nhm.ac.uk/research-curation/news-events/seminars/

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Rebecca Upson, UK Overseas Territories team, The Herbarium, Royal Botanic Gardens Kew

 

Friday 28 November 11:00  Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)

 

The Falkland Islands are predicted to experience a 3°C temperature rise in mean annual temperature over the coming century, six times the rate of warming over the last 100 years.

NaturalHistoryMuseum_PictureLibrary_055327_IA.jpgOur study is the first to investigate the likely vulnerability of a suite of range-restricted species whose distributions are associated with broad climatic trends across the archipelago. We had a particular focus on assessing the effectiveness of the current protected areas network and identifying refugia sites for those species at risk.

 

More information on attending seminars at http://www.nhm.ac.uk/research-curation/news-events/seminars/

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LIFE SCIENCES DEPARTMENT SEMINAR

 

British Butterfly.jpg

 

 

 

Using the NHM collections to track the long-term seasonal response of British butterflies to climate change

 

Steve Brooks

Department of Life Sciences, NHM

 

Wednesday 29 January 11:00

Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)

 

 

Changes in the emergence dates of British butterflies have been documented from observational monitoring data which mostly date from the 1970s. Few data, however, are currently available to extend the baseline to the period before the onset of rapid climate change. An important, but neglected, source of information is available in the NHM collections, which can extend this record to the mid-19th century. Our results show that British butterfly collection data reflect phenological responses to temperature. First collection dates of museum specimens advance during warm years and retreat during cold years. Rates of change, however, appear to be slowing in some species, when compared to recent observational data, suggesting some species may be approaching the limits of phenological advancement. Steve Brooks will discuss the potential  of the NHM collections to study the response of animals and plants to recent climate change.

 

 

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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Coral.jpg

 

Conservation of reef corals of the world: why phylogeny matters


Danwei Huang

Postdoctoral scholar, University of Iowa

 

Friday 18 October 11:00
Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)


One third of the world's reef-building corals are facing heightened extinction risk from anthropogenic climate change and local impacts. Extinction probabilities aside, species are not equal. Rather, evolutionary processes render each species, or species assemblage in general, unique with a distinctive history that can be characterised for conservation. My research is aimed at quantifying these patterns based on a robust understanding of the coral tree of life. In this talk, I will show that it is critical to consider species' contribution to evolutionary diversity in conjunction with their extinction risk when setting priorities to safeguard biodiversity.

 

My analyses identify the most endangered lineages that would not be given top priority on the basis of risk alone, and further demonstrate that corals susceptible to impacts such as bleaching and disease tend to be close relatives. One of Earth's most threatened reef regions, the Coral Triangle, is also famously the most biodiverse. While competing ideas are plentiful, the dynamics underlying this biogeographic pattern remain poorly understood. Phylogenetic modelling adds a valuable dimension to these explanations, and can help us uncover the evolutionary processes that have shaped coral richness in the hotspot. Indeed, conservation of the world's reef corals requires protecting the historical sources of diversity, particularly the evolutionarily distinct species and the drivers of its geographic diversity gradient.

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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Wednesday 17 of April 11:00

Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)

 

Studying the impacts of climate change and ocean acidification on calcified macroalgae: why, how and what we have we found

 

Chris Williamson

Genomics & Microbes, Dept of Life Sciences, NHM and School of Earth and Ocean Sciences, Cardiff University

 

 

Climate change and ocean acidification (OA) are causing increased sea surface temperatures and decreased pH / carbonate saturation, respectively, in the marine environment. Almost all marine species are likely to be impacted in some respect by these changes, with calcifying species predicted to be the most vulnerable. Calcifying macroalgae of the red algal genusCorallina are widely distributed and important autogenic ecosystem engineers, providing habitat for numerous small invertebrate species, shelter from the stresses of intertidal life, and surfaces for the settlement of microphytobenthos. Given the particular skeletal mineralogy of these species, i.e. high Mg-calcite CaCO3, they are predicted to be among the first responders to OA. A research project is therefore being undertaken to examine the potential impacts of climate change and OA on Corallina species in the northeastern Atlantic. An approach has been adopted to allow examination of potential impacts in the context of present day and very recent past conditions. This seminar will present information on the approach employed (use of herbarium collections, seasonal northeastern Atlantic sampling), methodologies used (X-Ray Diffraction, PAM-fluorescence, SEM, molecular techniques), and results gained thus far (seasonal skeletal mineralogy cycles, carbonate chemistry experienced in situ, photophysiology). Plans for the next stage of the project (future scenario incubations) will also be presented, highlighting how lessons learnt thus far will inform this future work.

 

 

 

Friday 19 of April 11:00

Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)

 

 

Forest understorey plant dynamics in the face of global environmental change

 

Pieter De Frenne

Forest & Nature Lab, Department of Forest and Water Management, Ghent University

 

 

Habitat change, eutrophication and climate change, among other global-change factors, have elevated the rate of species’ extinction to a level on par with historical mass extinction events. In temperate forests specifically, biodiversity is mainly a function of the herbaceous understorey community. Many forest understorey plants, however, are not able to track habitat change and the shifting climate due to their limited colonisation capacity. Their acclimation potential within their occupied habitats will likely determine their short- and long-term persistence. The response of plants to N deposition, however, diverges between forests and other ecosystems, probably due to the greater structural complexity and pivotal role of light availability in forests. A potential new pressure on forest biodiversity is the increasing demand for woody biomass due to the transitions to more biobased economies. Elevated wood extraction could result in increased canopy opening and understorey species shifts. To date, the outcome of climate warming and changing forest management (resulting in altered light availability) in forests experiencing decades of elevated N inputs remains uncertain. I will present our research on the (interactive) effects of climate warming, enhanced N inputs, and management-driven forest floor light availability on the growth and reproduction of a selection of understorey forest plant species, and (ii) the composition and diversity of understorey plant communities in European and eastern North American temperate forests.

 

 

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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Steve Brooks from the Museum and collaborators from UCL, the universities of Nottingham, Bergen and Liverpool, and the RSPB have been examining reasons for the breeding success of the Slavonian grebe Podiceps auritus. The Slavonian grebe has a UK breeding population of only 29 pairs, found in NE Scotland only since 1908.  Loch Ruthven holds the largest British population in an RSPB reserve and breeding success is known to have fluctuated annually since records began in 1970.

 

Slavonian grebe audubon (c) NHM small.jpgSlavonian grebe from Audubon's Birds of America    © Natural History Museum

 

 

The research looked at whether the fluctuations are linked to the numbers of chironomids, the group of flies on which Steve is an expert.  These midges are an important food-source for the grebe chicks.

 

The team analysed a sediment core from the lake by slicing it into 2.5-mm sections to separate sediment on a yearly basis.  In this sediment, they looked at the remains of chironomids, diatoms (planktonic algae which show strong seasonal trends in populations) and algal pigments.   These plant data were used to deduce changes in total phosphorus in the water and to see whether there was a link between algae and the abundance of chironomids. Trends in grebe breeding success, chironomid abundance and algal populations were analysed against climate data to clarify whether climate was the key factor behind all of these fluctuations.

 

The study shows that grebe breeding success is linked with chironomid abundance and chironomid abundance is linked with total phosphorus. Over the past 100 years, lake productivity and chironomid abundance have both risen, increasing more rapidly from the mid-twentieth century to the present. Fluctuations in grebe breeding success from 1970 followed the same pattern as chironomid variation, with a lag of one year. 

 

One of the questions of interest was whether grebe breeding success was influenced by climate variability year by year.  Because the Slavonian grebe is a relative newcomer to the UK, it is not clear how vulnerable this small population is to environmental change.  However. No correlation was found between grebe productivity or chironomid abundance and climate.  The team concludes that breeding success of the grebe depends on food availability in the form of chironomids at Loch Ruthven.

 

Brooks, SJ et al. Population trends in the Slavonian grebe Podiceps  auritus (L.) and Chironomidae (Diptera) at a Scottish loch  Journal of  Paleolimnology April 2012, Volume 47 (4) 631-644  doi: 10.1007/s10933-012-9587-4

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Just a quick link through to a NERC blog on the use of Araucaria trees in investigating plant responses to higher carbon dioxide levels. The visiting researchers used NHM botany collections and those of a number of other institutions, in addition to growing and experimenting on living plants.

 

Araucaria includes the familar garden Monkey Puzzle tree and are part of a group of plants that reached its maximum diversity during the Jurassic and Cretaceous periods between 200 and 65 million years ago.  It is known that in conditions of higher or lower carbon dioxide, plants will have different numbers of gas-exchange pores (stomata) on their leaves.  The interest of Araucaria lies in whether the number of stomata in fossils can be used to understand more about past patterns of carbon dioxide variation and hence climate change linked to atmospheric changes.

 

araucaria NaturalHistoryMuseum_015374_IA.jpg

Fossil Araucaria cones from the Jurassic

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Why collect? Do we need more? Why keep such large collections?  What is the relevance to modern science? Having a collection of around 70 million objects that has been growing since 1753 means that we get asked these questions from time to time.

 

In essence, the reason is that science relies upon physical evidence: we want to see for ourselves. Scientists are trained to be sceptical: to question ideas; to measure and re-examine data; to look at what is known through new eyes; and to pursue what is not yet known. This is fundamentally what natural history is about. The “natural” in natural history is not a direct reference to our modern ideas of nature, although it includes living things and the geological.  Instead it refers to what is real, physical, observable, measurable. The “history” means investigation, or account—so natural history is about investigating real things.

 

That’s why we collect—this and other massive collections represent natural diversity—a resource that has been developed by thousands of people all over the world for three hundred years. So we are developing an intellectual and scientific capital, a bank of evidence and ideas that connect to what has been found out through science in the past and that can be re-examined and questioned.

 

Crucially, although they were developed usually to investigate the diversity of species, the collections can also be used to ask new questions about issues of new concern.  There is huge current interest in natural diversity and how organisms enable ecosystems to function, but what about issues such as climate change? A group of scientists in the Museum have been looking again at the collections to assess their value in understanding how the biosphere—the totality of living things—responds to climate change. 

 

They have just produced a paper in BioScience (Johnson et al. 2011) that outlines the value of collections and points to new directions for scientific collaboration and collections development to answer climate change questions and predict future trends in the impacts on living things.

 

In particular, there is interest in our collection in terms of:

 

  • Investigating how geographical distribution changed in the past as climate changed, using location and dates of collection;
  • Understanding how extinction of species and populations has happened in the past as climate changed—so mammoths were reduced to small populations that clung on in some locations for long periods even after climate had reduced their range of distribution;
  • Looking at how flowering times have changed over time—plants are collected as they flower in many cases and the dates of flowering with respect to temperature can be tracked;
  • Examining changes in diet as climate changes—different diets leave traces in bone and other tissue. Changes in food sources may reduce survival.
  • Understanding changes in genetic diversity from DNA as populations respond to environmental change

 

There are many other possibilities and the challenge for the Museum is to enable its own and collaborating scientists to work effectively with the collection in new ways to answer these questions. We also need to think about what is collected now, and how it is stored; and think about how information on collections is best stored on databases to allow research to take place. This is an opportunity for a wide network of museums that will also need to work with other scientific collections to provide the evidence to understand the future.

 

Kenneth G. Johnson, Stephen J. Brooks, Phillip B. Fenberg, Adrian G. Glover, Karen E. James, Adrian M. Lister, Ellinor Michel, Mark Spencer, Jonathan A. Todd, Eugenia Valsami-Jones, Jeremy R. Young, John R. Stewart Climate Change and Biosphere Response: Unlocking the Collections Vault (pp. 147-153) DOI: 10.1525/bio.2011.61.2.10 Stable URL: http://www.jstor.org/stable/10.1525/bio.2011.61.2.10

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The Museum's collections are used for research by more than 8,000 visiting scientists each year, and many thousands of specimens are sent on loan to other institutions for research purposes.

 

Scientists from the University of East Anglia, the Royal Botanic Gardens, Kew, and the Universities of Sussex and Kent have used the NHM botany collections and those of other institutions to look at how the flowering time of orchids varies with spring temperatures.  They looked at recent field records of flowering date and temperature (1975-2006) for the UK Early Spider Orchid, Ophrys sphegodes, and compared these with historical temperature records and dated flowering specimens in collections (1848-1958).

 

Their research, published in the Journal of Ecology, showed that the orchids responded to temperature in the same way in the two periods.  This means that collection specimens could be of significant value in looking at the responses of plants to past climate patterns for periods when there were no records kept of flowering dates.

 

This work indicates the potential value of collections for investigating ecological responses to climate and as research resources for new scientific interests.

 

 

Karen M. Robbirt, Anthony J. Davy, Michael J. Hutchings and David L. Roberts (2011) Validation of biological collections as a source of phenological data for use in climate change studies: a case study with the orchid Ophrys sphegodes. Journal of Ecology, 99, 235–241 doi: 10.1111/j.1365-2745.2010.01727.x

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Bryozoans are colonial invertebrates, commonly found attached to hard surfaces from the shallow subtidal zone to the deep sea. Bryozoan colonies increase in size by the budding of the numerous individuals (zooids) that make up the colony.

 

A collaborative team, including Professor Beth Okamura, Dr Tanya Knowles and Dr Paul Taylor from the NHM, explored how the size of zooids in fossil bryozoans varied as temperature changed.  This enabled them to use bryozoans to deduce the annual ranges of temperature during the Early Pliocene (around 4 million to 5.5 million years ago) in the Weddell Sea off the coast of  Antarctica.

 

Their results show that during this period the climate was warmer than that of the present day, suggesting an ice-free environment in that part of Antarctica.

 

The research shows the value of fossil bryozoans from shallow seas as a tool for reconstructing seasonal variation in climate in near-polar latitudes in past periods of the Earth's history.  This helps to understand how climates have changed naturally in the past - knowledge that in turn enables present-day changes in climate to be understood and predicted.

 

Clark, N., Williams, M., Okamura, B., Smellie, J., Nelson, A., Knowles, T., Taylor, P., Leng, M., Zalasiewicz, J. & Hayward, A. 2010. Early Pliocene Weddell Sea seasonality determined from bryozoans. Stratigraphy 7: 199-206.