lnu.sePublications
Change search
Link to record
Permanent link

Direct link
Gaillard, Marie-JoséORCID iD iconorcid.org/0000-0002-2025-410X
Alternative names
Publications (10 of 183) Show all publications
Vinogradova, O., Gaillard, M.-J., Andren, E., Palm, V., Rönnby, J., Dahl, M., . . . Andren, T. (2024). 3000 Years of past regional and local land-use and land-cover change in the southeastern Swedish coastal area: Early human-induced increases in landscape openness as a potential nutrient source to the Baltic Sea coastal waters. The Holocene, 34(1), 56-73
Open this publication in new window or tab >>3000 Years of past regional and local land-use and land-cover change in the southeastern Swedish coastal area: Early human-induced increases in landscape openness as a potential nutrient source to the Baltic Sea coastal waters
Show others...
2024 (English)In: The Holocene, ISSN 0959-6836, E-ISSN 1477-0911, Vol. 34, no 1, p. 56-73Article in journal (Refereed) Published
Abstract [en]

Reconstructions of past land use and related land-cover changes at local and regional scales are needed to evaluate the potential long-term impacts of land use on the coastal waters of the Baltic Sea. In this purpose, we selected the Gamleby area at the Swedish Baltic Sea coast for a case study. We use a new, high resolution pollen record from a small lake (Lillsjon) located 3.6 km NNW of the bay Gamlebyviken and detailed analysis of the available archeological data to reconstruct local land-use changes over the last 3000 years. To estimate land-cover change at local (2-3 km radius area) and regional (50 km radius area) scales we use four additional, published pollen records from two small and two large lakes (25-70 km S of Lillsjon) and the Landscape Reconstruction Algorithm, a pollen-vegetation modeling scheme. Results show that regional and local (small lakes Lillsjon and Hyttegol) land-cover changes are comparable over the last 1500 years (Late Iron Age to present), and that landscape openness was much larger locally than regionally (difference of 20-40% cover over the last 500 years). The periods of largest potential impacts on the Gamlebyviken Bay from regional and local land use are 200-950 CE (Late Iron Age) and 1450 CE to present, and of lowest potential impacts 950-1450 CE. The question on whether the large landscape openness 1150-50 BCE and significant afforestation 50 BCE-200 CE reconstructed for Lillsjon's area are characteristic of the Gamlebyviken region will require additional pollen records in the catchment area.

Place, publisher, year, edition, pages
Sage Publications, 2024
Keywords
Archeological data, Gamlebyviken, Landscape Reconstruction Algorithm, Late Holocene, pollen analysis, REVEALS and LOVE models
National Category
Physical Geography
Research subject
Environmental Science, Paleoecology
Identifiers
urn:nbn:se:lnu:diva-125504 (URN)10.1177/09596836231200433 (DOI)001084189400001 ()2-s2.0-85174272828 (Scopus ID)
Available from: 2023-11-06 Created: 2023-11-06 Last updated: 2024-02-27Bibliographically approved
Strandberg, G., Chen, J., Fyfe, R., Kjellstrom, E., Lindström, J., Poska, A., . . . Gaillard, M.-J. (2023). Did the Bronze Age deforestation of Europe affect its climate?: A regional climate model study using pollen-based land cover reconstructions. Climate of the Past, 19(7), 1507-1530
Open this publication in new window or tab >>Did the Bronze Age deforestation of Europe affect its climate?: A regional climate model study using pollen-based land cover reconstructions
Show others...
2023 (English)In: Climate of the Past, ISSN 1814-9324, E-ISSN 1814-9332, Vol. 19, no 7, p. 1507-1530Article in journal (Refereed) Published
Abstract [en]

This paper studies the impact of land use and land cover change (LULCC) on the climate around 2500 years ago (2.5 ka), a period of rapid transitions across the European landscape. One global climate model was used to force two regional climate models (RCMs). The RCMs used two land cover descriptions. The first was from a dynamical vegetation model representing potential land cover, and the second was from a land cover description reconstructed from pollen data by statistical interpolation. The two different land covers enable us to study the impact of land cover on climate conditions. Since the difference in landscape openness between potential and reconstructed land cover is mostly due to LULCC, this can be taken as a measure of early anthropogenic effects on climate. Since the sensitivity to LULCC is dependent on the choice of climate model, we also use two RCMs. The results show that the simulated 2.5 ka climate was warmer than the simulated pre-industrial (PI, 1850 CE) climate. The largest differences are seen in northern Europe, where the 2.5 ka climate is 2-4 degrees C warmer than the PI period. In summer, the difference between the simulated 2.5 ka and PI climates is smaller (0-3 degrees C), with the smallest differences in southern Europe. Differences in seasonal precipitation are mostly within +/- 10 %. In parts of northern Europe, the 2.5 ka climate is up to 30% wetter in winter than that of the PI climate. In summer there is a tendency for the 2.5 ka climate to be drier than the PI climate in the Mediterranean region. The results also suggest that LULCC at 2.5 ka impacted the climate in parts of Europe. Simulations including reconstructed LULCC (i.e. those using pollen-derived land cover descriptions) give up to 1 degrees C higher temperature in parts of northern Europe in winter and up to 1.5 degrees C warmer in southern Europe in summer than simulations with potential land cover. Although the results are model dependent, the relatively strong response implies that anthropogenic land cover changes that had occurred during the Neolithic and Bronze Age could have affected the European climate by 2.5 ka.

Place, publisher, year, edition, pages
Copernicus Publications, 2023
National Category
Physical Geography Climate Research
Research subject
Environmental Science, Paleoecology
Identifiers
urn:nbn:se:lnu:diva-123890 (URN)10.5194/cp-19-1507-2023 (DOI)001037762400001 ()2-s2.0-85167663006 (Scopus ID)
Available from: 2023-08-25 Created: 2023-08-25 Last updated: 2023-11-07Bibliographically approved
Li, F., Gaillard, M.-J., Xie, S., Huang, K., Cui, Q., Fyfe, R., . . . Sugita, S. (2023). Evaluation of relative pollen productivities in temperate China for reliable pollen-based quantitative reconstructions of Holocene plant cover. Frontiers in Plant Science, 14, Article ID 1240485.
Open this publication in new window or tab >>Evaluation of relative pollen productivities in temperate China for reliable pollen-based quantitative reconstructions of Holocene plant cover
Show others...
2023 (English)In: Frontiers in Plant Science, E-ISSN 1664-462X, Vol. 14, article id 1240485Article in journal (Refereed) Published
Abstract [en]

The Landscape Reconstruction Algorithm (LRA) is regarded as the soundest approach for quantifying taxon-specific plant cover from pollen data. The reliability of relative pollen productivity (RPP) estimates is fundamental in the accuracy of quantitative vegetation reconstruction using the LRA approach. Inconsistent RPP estimates produced by different studies can cast doubt on the reliability and applicability of quantitative vegetation reconstruction. Therefore, it is crucial that the RPP estimates are evaluated before being applied for quantitative vegetation reconstruction. We have tested two alternative approaches, namely, a leave-one-out cross-validation (LOO) method and a splitting-by-subregion strategy, using surface pollen assemblages and the REVEALS model-the first step in the LRA-to evaluate the reliability of RPPs estimates of 10 target taxa obtained in the cultural landscape of Shandong. We compared the REVEALS estimates (RVs) with observations of regional vegetation abundance (OBVs) and pollen proportions (PPs). The RVs of all taxa are generally closer to OBVs than PPs, and the degree of similarity depends strongly on the abundance of individual taxa in plant and pollen; taxa dominant in the region show the highest similarity between RVs and OBVs, such as Artemisia, Poaceae, and Humulus. The RVs of all herb taxa except Humulus and Asteraceae SF Cichorioideae are slightly overrepresented, and the RVs of all tree taxa are underrepresented except for Castanea. The comparison of RVs with OBVs collected from different spatial extents shows that the RVs of all herb taxa are more similar to OBVs collected from shorter distances (100 km and 75 km for the entire region and the subregion, respectively), whereas the RVs of all tree taxa are more similar to OBVs collected from longer distances (150 km and 100 km for the entire region and the subregion, respectively). Furthermore, our findings highlight the importance to test different sizes of area for vegetation surveys for evaluation of the RVs given that the appropriate size of vegetation survey may vary between low pollen producers (mainly herbs) and high pollen producers (mainly trees). We consider that the LOO strategy is the best approach in this case study for evaluating the RPP estimates from surface moss polsters. The evaluation confirms the reliability of the obtained RPP estimates for their potential application in quantitative reconstruction of vegetation abundance in temperate China.

Place, publisher, year, edition, pages
Frontiers Media S.A., 2023
Keywords
China, relative pollen productivity, evaluation, observation of regional vegetation, REVEALS model
National Category
Ecology
Research subject
Environmental Science, Paleoecology
Identifiers
urn:nbn:se:lnu:diva-126033 (URN)10.3389/fpls.2023.1240485 (DOI)001104336700001 ()38023872 (PubMedID)2-s2.0-85177444321 (Scopus ID)
Available from: 2023-12-18 Created: 2023-12-18 Last updated: 2024-02-15Bibliographically approved
Li, F., Gaillard, M.-J., Cao, X., Herzschuh, U., Sugita, S., Ni, J., . . . Yao, Y. (2023). Gridded pollen-based Holocene regional plant cover in temperate and northernsubtropical China suitable for climate modelling. Earth System Science Data, 15(1), 95-112
Open this publication in new window or tab >>Gridded pollen-based Holocene regional plant cover in temperate and northernsubtropical China suitable for climate modelling
Show others...
2023 (English)In: Earth System Science Data, ISSN 1866-3508, E-ISSN 1866-3516, Vol. 15, no 1, p. 95-112Article in journal (Refereed) Published
Abstract [en]

We present the first gridded and temporally continuous quantitative pollen-based plant-cover reconstruction for temperate and northern subtropical China over the Holocene (11.7 ka to present) obtained by applying the Regional Estimates of VEgetation Abundance from Large Sites (REVEALS) model. The objective is to provide a dataset of pollen-based land cover for the last ca. 12 millennia that is suitable for palaeoclimate modelling and for the evaluation of simulated past vegetation cover from dynamic vegetation models and anthropogenic land-cover change (ALCC) scenarios. The REVEALS reconstruction was achieved using 94 selected pollen records from lakes and bogs at a 1 degrees x 1 degrees spatial scale and a temporal resolution of 500 years between 11.7 and 0.7 ka and in three recent time windows (0.7-0.35 ka, 0.35-0.1 ka, and 0.1 ka to present). The dataset includes REVEALS estimates of cover and their standard errors (SEs) for 27 plant taxa in 75 1 degrees x 1 degrees grid cells distributed within the study region. The 27 plant taxa were also grouped into 6 plant functional types and 3 land-cover types (coniferous trees CT, broadleaved trees BT, and C-3 herbs/open land (C3H/OL)), and their REVEALS estimates of cover and related SEs were calculated. We describe the protocol used for the selection of pollen records and the REVEALS application (with parameter settings) and explain the major rationales behind the protocol. As an illustration, we present, for eight selected time windows, gridded maps of the pollen-based REVEALS estimates of cover for the three land-cover types (CT, BT, and C3H/OL). We then discuss the reliability and limitations of the Chinese dataset of Holocene gridded REVEALS plant cover, and its current and potential uses. The dataset is available at the National Tibetan Plateau Data Center (TPDC; Li, 2022; ).

Place, publisher, year, edition, pages
Copernicus Publications, 2023
National Category
Physical Geography
Research subject
Environmental Science, Paleoecology
Identifiers
urn:nbn:se:lnu:diva-118838 (URN)10.5194/essd-15-95-2023 (DOI)000908975800001 ()2-s2.0-85147270968 (Scopus ID)
Available from: 2023-01-30 Created: 2023-01-30 Last updated: 2023-02-17Bibliographically approved
Dallmeyer, A., Poska, A., Marquer, L., Seim, A. & Gaillard, M.-J. (2023). Holocene forest-cover changes in Europe - a comparison of dynamic vegetation model results and pollen-based REVEALS reconstructions. In: EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-11206: . Paper presented at EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023. European Geosciences Union (EGU)
Open this publication in new window or tab >>Holocene forest-cover changes in Europe - a comparison of dynamic vegetation model results and pollen-based REVEALS reconstructions
Show others...
2023 (English)In: EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-11206, European Geosciences Union (EGU), 2023Conference paper, Oral presentation with published abstract (Refereed)
Abstract [en]

We compare Holocene forest-cover changes in Europe derived from a transient MPI-ESM1.2 simulation with high spatial resolution time-slice simulations conducted in LPJ-GUESS and pollen-based quantitative reconstructions of forest cover based on the REVEALS model (pol-RVs). The dynamic vegetation models and pol-RVs agree with respect to the general temporal trends in forest cover for most parts of Europe, with a large forest cover during the mid-Holocene and substantially smaller forest cover closer to the present time. However, the age of the start of decrease in forest cover varies between regions, and is much older in the pol-RVs than in the models. The pol-RVs suggest much earlier anthropogenic deforestation than the prescribed land-use in the models starting 2000 years ago. While LPJ-GUESS generally overestimates forest cover compared to pol-RVs, MPI-ESM indicates lower percentages of forest cover than pol-RVs, particularly in Central Europe. A comparison of the simulated climate with chironomid-based climate reconstructions reveal that model-data mismatches in forest cover are in most cases not driven by biases in the climate. Instead, sensitivity experiments show that the model results strongly depend on the models tuning regarding natural disturbance regimes (e.g. fire and wind throw). The frequency and strength of disturbances are – like most of the parameters in the vegetation models – static and calibrated to modern conditions. However, these parameter values may not be valid during climate and vegetation states totally different from today’s. In particular, the mid-Holocene natural forests were probably more stable and less sensitive to disturbances than present day forests that are heavily altered by human interventions. Our analysis highlights the fact that such model settings are inappropriate for paleo-simulations and complicate model-data comparisons with additional challenges. Moreover, our study suggests that land-use is the main driver of forest decline in Europe during the mid- and late-Holocene.

Place, publisher, year, edition, pages
European Geosciences Union (EGU), 2023
National Category
Ecology
Research subject
Environmental Science, Paleoecology
Identifiers
urn:nbn:se:lnu:diva-126783 (URN)10.5194/egusphere-egu23-11206 (DOI)
Conference
EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023
Available from: 2024-01-16 Created: 2024-01-16 Last updated: 2024-02-28Bibliographically approved
Sim, T. G., Swindles, G. T., Morris, P. J., Baird, A. J., V. Gallego-Sala, A., Wang, Y., . . . Zhang, H. (2023). Regional variability in peatland burning at mid-to high-latitudes during the Holocene. Quaternary Science Reviews, 305, Article ID 108020.
Open this publication in new window or tab >>Regional variability in peatland burning at mid-to high-latitudes during the Holocene
Show others...
2023 (English)In: Quaternary Science Reviews, ISSN 0277-3791, E-ISSN 1873-457X, Vol. 305, article id 108020Article in journal (Refereed) Published
Abstract [en]

Northern peatlands store globally-important amounts of carbon in the form of partly decomposed plant detritus. Drying associated with climate and land-use change may lead to increased fire frequency and severity in peatlands and the rapid loss of carbon to the atmosphere. However, our understanding of the patterns and drivers of peatland burning on an appropriate decadal to millennial timescale relies heavily on individual site-based reconstructions. For the first time, we synthesise peatland macrocharcoal re-cords from across North America, Europe, and Patagonia to reveal regional variation in peatland burning during the Holocene. We used an existing database of proximal sedimentary charcoal to represent regional burning trends in the wider landscape for each region. Long-term trends in peatland burning appear to be largely climate driven, with human activities likely having an increasing influence in the late Holocene. Warmer conditions during the Holocene Thermal Maximum (similar to 9e6 cal. ka BP) were associated with greater peatland burning in North America's Atlantic coast, southern Scandinavia and the Baltics, and Patagonia. Since the Little Ice Age, peatland burning has declined across North America and in some areas of Europe. This decline is mirrored by a decrease in wider landscape burning in some, but not all sub-regions, linked to fire-suppression policies, and landscape fragmentation caused by agricultural expansion. Peatlands demonstrate lower susceptibility to burning than the wider landscape in several instances, probably because of autogenic processes that maintain high levels of near-surface wetness even during drought. Nonetheless, widespread drying and degradation of peatlands, particularly in Europe, has likely increased their vulnerability to burning in recent centuries. Consequently, peatland restoration efforts are important to mitigate the risk of peatland fire under a changing climate. Finally, we make recommendations for future research to improve our understanding of the controls on peatland fires.(c) 2023 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Place, publisher, year, edition, pages
Elsevier, 2023
Keywords
Fire, Charcoal, Palaeofire, Palaeoenvironments, Data analysis, North America, Europe, Patagonia, Carbon balance, Drought
National Category
Ecology
Research subject
Environmental Science, Paleoecology
Identifiers
urn:nbn:se:lnu:diva-120970 (URN)10.1016/j.quascirev.2023.108020 (DOI)000976516600001 ()2-s2.0-85149824046 (Scopus ID)
Available from: 2023-05-26 Created: 2023-05-26 Last updated: 2023-09-07Bibliographically approved
Serge, M. A., Mazier, F., Fyfe, R., Gaillard, M.-J., Klein, T., Lagnoux, A., . . . Zernitskaya, V. P. (2023). Testing the Effect of Relative Pollen Productivity on the REVEALS Model: A Validated Reconstruction of Europe-Wide Holocene Vegetation. Land, 12(5), Article ID 986.
Open this publication in new window or tab >>Testing the Effect of Relative Pollen Productivity on the REVEALS Model: A Validated Reconstruction of Europe-Wide Holocene Vegetation
Show others...
2023 (English)In: Land, E-ISSN 2073-445X, Vol. 12, no 5, article id 986Article in journal (Refereed) Published
Abstract [en]

Reliable quantitative vegetation reconstructions for Europe during the Holocene are crucial to improving our understanding of landscape dynamics, making it possible to assess the past effects of environmental variables and land-use change on ecosystems and biodiversity, and mitigating their effects in the future. We present here the most spatially extensive and temporally continuous pollen-based reconstructions of plant cover in Europe (at a spatial resolution of 1 degrees x 1 degrees) over the Holocene (last 11.7 ka BP) using the 'Regional Estimates of VEgetation Abundance from Large Sites' (REVEALS) model. This study has three main aims. First, to present the most accurate and reliable generation of REVEALS reconstructions across Europe so far. This has been achieved by including a larger number of pollen records compared to former analyses, in particular from the Mediterranean area. Second, to discuss methodological issues in the quantification of past land cover by using alternative datasets of relative pollen productivities (RPPs), one of the key input parameters of REVEALS, to test model sensitivity. Finally, to validate our reconstructions with the global forest change dataset. The results suggest that the RPPs.st1 (31 taxa) dataset is best suited to producing regional vegetation cover estimates for Europe. These reconstructions offer a long-term perspective providing unique possibilities to explore spatial-temporal changes in past land cover and biodiversity.

Place, publisher, year, edition, pages
MDPI, 2023
Keywords
Europe, quantitative past land cover, Holocene, pollen data, REVEALS model, relative pollen productivity, validation
National Category
Geology Ecology Physical Geography
Research subject
Environmental Science, Paleoecology
Identifiers
urn:nbn:se:lnu:diva-123666 (URN)10.3390/land12050986 (DOI)001009021000001 ()2-s2.0-85160569864 (Scopus ID)
Available from: 2023-08-14 Created: 2023-08-14 Last updated: 2023-09-07Bibliographically approved
Dallmeyer, A., Poska, A., Marquer, L., Seim, A. & Gaillard, M.-J. (2023). The challenge of comparing pollen-based quantitative vegetation reconstructions with outputs from vegetation models - a European perspective. Climate of the Past, 19(7), 1531-1557
Open this publication in new window or tab >>The challenge of comparing pollen-based quantitative vegetation reconstructions with outputs from vegetation models - a European perspective
Show others...
2023 (English)In: Climate of the Past, ISSN 1814-9324, E-ISSN 1814-9332, Vol. 19, no 7, p. 1531-1557Article in journal (Refereed) Published
Abstract [en]

We compare Holocene tree cover changes in Europe derived from a transient Earth system model simulation (Max Planck Institute Earth System Model - MPI-ESM1.2, including the land surface and dynamic vegetation model JSBACH) with high-spatial-resolution time slice simulations performed in the dynamic vegetation model LPJ-GUESS (Lund-Potsdam-Jena General Ecosystem Simulator) and pollen-based quantitative reconstructions of tree cover based on the REVEALS (Regional Estimates of Vegetation Abundance from Large Sites) model. The dynamic vegetation models and REVEALS agree with respect to the general temporal trends in tree cover for most parts of Europe, with a large tree cover during the mid-Holocene and a substantially smaller tree cover closer to the present time. However, the decrease in tree cover in REVEALS starts much earlier than in the models, indicating much earlier anthropogenic deforestation than the prescribed land use in the models. While LPJ-GUESS generally overestimates tree cover compared to the reconstructions, MPI-ESM indicates lower percentages of tree cover than REVEALS, particularly in central Europe and the British Isles. A comparison of the simulated climate with chironomid-based climate reconstructions reveals that model-data mismatches in tree cover are in most cases not driven by biases in the climate. Instead, sensitivity experiments indicate that the model results strongly depend on the tuning of the models regarding natural disturbance regimes (e.g. fire and wind throw). The frequency and strength of disturbances are - like most of the parameters in the vegetation models - static and calibrated to modern conditions. However, these parameter values may not be valid for past climate and vegetation states totally different from today's. In particular, the mid-Holocene natural forests were probably more stable and less sensitive to disturbances than present-day forests that are heavily altered by human interventions. Our analysis highlights the fact that such model settings are inappropriate for paleo-simulations and complicate model-data comparisons with additional challenges. Moreover, our study suggests that land use is the main driver of forest decline in Europe during the mid-Holocene and late Holocene.

Place, publisher, year, edition, pages
Copernicus Publications, 2023
National Category
Physical Geography
Research subject
Environmental Science, Paleoecology
Identifiers
urn:nbn:se:lnu:diva-123786 (URN)10.5194/cp-19-1531-2023 (DOI)001038108000001 ()2-s2.0-85170833178 (Scopus ID)
Available from: 2023-08-17 Created: 2023-08-17 Last updated: 2023-11-21Bibliographically approved
Githumbi, E., Fyfe, R., Gaillard, M.-J., Trondman, A.-K., Mazier, F., Nielsen, A.-B., . . . Shumilovskikh, L. (2022). European pollen-based REVEALS land-cover reconstructions for the Holocene: methodology, mapping and potentials. Earth System Science Data, 14(4), 1581-1619
Open this publication in new window or tab >>European pollen-based REVEALS land-cover reconstructions for the Holocene: methodology, mapping and potentials
Show others...
2022 (English)In: Earth System Science Data, ISSN 1866-3508, E-ISSN 1866-3516, Vol. 14, no 4, p. 1581-1619Article in journal (Refereed) Published
Abstract [en]

Quantitative reconstructions of past land cover are necessary to determine the processes involved in climate-human-land-cover interactions. We present the first temporally continuous and most spatially extensive pollen-based land-cover reconstruction for Europe over the Holocene (last 11 700 cal yr BP). We describe how vegetation cover has been quantified from pollen records at a 1 degrees x 1 degrees spatial scale using the "Regional Estimates of VEgetation Abundance from Large Sites" (REVEALS) model. REVEALS calculates estimates of past regional vegetation cover in proportions or percentages. REVEALS has been applied to 1128 pollen records across Europe and part of the eastern Mediterranean-Black Sea-Caspian corridor (30-75 degrees N, 25 degrees W-50 degrees E) to reconstruct the percentage cover of 31 plant taxa assigned to 12 plant functional types (PFTs) and 3 land-cover types (LCTs). A new synthesis of relative pollen productivities (RPPs) for European plant taxa was performed for this reconstruction. It includes multiple RPP values (>= 2 values) for 39 taxa and single values for 15 taxa (total of 54 taxa). To illustrate this, we present distribution maps for five taxa (Calluna vulgaris, Cerealia type (t)., Picea abies, deciduous Quercus t. and evergreen Quercus t.) and three land-cover types (open land, OL; evergreen trees, ETs; and summer-green trees, STs) for eight selected time windows. The reliability of the REVEALS reconstructions and issues related to the interpretation of the results in terms of landscape openness and human-induced vegetation change are discussed. This is followed by a review of the current use of this reconstruction and its future potential utility and development. REVEALS data quality are primarily determined by pollen count data (pollen count and sample, pollen identification, and chronology) and site type and number (lake or bog, large or small, one site vs. multiple sites) used for REVEALS analysis (for each grid cell). A large number of sites with high-quality pollen count data will produce more reliable land-cover estimates with lower standard errors compared to a low number of sites with lower-quality pollen count data. The REVEALS data presented here can be downloaded from https://doi.org/10.1594/PANGAEA.937075 (Fyfe et al., 2022).

Place, publisher, year, edition, pages
Copernicus Gesellschaft MBH, 2022
National Category
Ecology Physical Geography
Research subject
Environmental Science, Paleoecology
Identifiers
urn:nbn:se:lnu:diva-112984 (URN)10.5194/essd-14-1581-2022 (DOI)000792377000001 ()2-s2.0-85128759533 (Scopus ID)2022 (Local ID)2022 (Archive number)2022 (OAI)
Available from: 2022-05-23 Created: 2022-05-23 Last updated: 2023-02-17Bibliographically approved
Strandberg, G., Lindström, J., Poska, A., Zhang, Q., Fyfe, R., Githumbi, E., . . . Gaillard, M.-J. (2022). Mid-Holocene European climate revisited: New high-resolution regional climate model simulations using pollen-based land-cover. Quaternary Science Reviews, 281, Article ID 107431.
Open this publication in new window or tab >>Mid-Holocene European climate revisited: New high-resolution regional climate model simulations using pollen-based land-cover
Show others...
2022 (English)In: Quaternary Science Reviews, ISSN 0277-3791, E-ISSN 1873-457X, Vol. 281, article id 107431Article in journal (Refereed) Published
Abstract [en]

Land-cover changes have a clear impact on local climates via biophysical effects. European land cover has been affected by human activities for at least 6000 years, but possibly longer. It is thus highly probable that humans altered climate before the industrial revolution (AD1750-1850). In this study, climate and vegetation 6000 years (6 ka) ago is investigated using one global climate model, two regional climate models, one dynamical vegetation model, pollen-based reconstruction of past vegetation cover using a model of the pollen-vegetation relationship and a statistical model for spatial interpolation of the reconstructed land cover. This approach enables us to study 6 ka climate with potential natural and reconstructed land cover, and to determine how differences in land cover impact upon simulated climate. The use of two regional climate models enables us to discuss the robustness of the results. This is the first experiment with two regional climate models of simulated palaeo-climate based on regional climate models. Different estimates of 6 ka vegetation are constructed: simulated potential vegetation and reconstructed vegetation. Potential vegetation is the natural climate-induced vegetation as simulated by a dynamical vegetation model driven by climate conditions from a climate model. Bayesian spatial model interpolated point estimates of pollen-based plant abundances combined with estimates of climate-induced potential un-vegetated land cover were used for reconstructed vegetation. The simulated potential vegetation is heavily dominated by forests: evergreen coniferous forests dominate in northern and eastern Europe, while deciduous broadleaved forests dominate central and western Europe. In contrast, the reconstructed vegetation cover has a large component of open land in most of Europe. The simulated 6 ka climate using reconstructed vegetation was 0-5 degrees C warmer than the pre-industrial (PI) climate, depending on season and region. The largest differences are seen in north-eastern Europe in winter with about 4-6 degrees C, and the smallest differences (close to zero) in southwestern Europe in winter. The simulated 6 ka climate had 10-20% more precipitation than PI climate in northern Europe and 10-20% less precipitation in southern Europe in summer. The results are in reasonable agreement with proxy-based climate reconstructions and previous similar climate modelling studies. As expected, the global model and regional models indicate relatively similar climates albeit with regional differences indicating that, models response to land-cover changes differently. The results indicate that the anthropogenic land-cover changes, as given by the reconstructed vegetation, in this study are large enough to have a significant impact on climate. It is likely that anthropogenic impact on European climate via land-use change was already taking place at 6 ka. Our results suggest that anthropogenic land-cover changes at 6 ka lead to around 0.5 degrees C warmer in southern Europe in summer due to biogeophysical forcing. (C) 2022 The Authors. Published by Elsevier Ltd.

Place, publisher, year, edition, pages
Elsevier, 2022
Keywords
Paleoclimate, Global climate model, Dynamical vegetation model, Vegetation reconstruction, Spatial statistical models, Land-use and land-cover change, REVEALS, LPJ-GUESS, EC-Earth, RCA4, HCLIM
National Category
Climate Research Ecology
Research subject
Environmental Science, Paleoecology
Identifiers
urn:nbn:se:lnu:diva-111123 (URN)10.1016/j.quascirev.2022.107431 (DOI)000766925500007 ()2-s2.0-85125186971 (Scopus ID)2022 (Local ID)2022 (Archive number)2022 (OAI)
Available from: 2022-04-07 Created: 2022-04-07 Last updated: 2023-05-02Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-2025-410X

Search in DiVA

Show all publications