Jan Weckström
Biographic Data
| ID | 6016968 |
|---|---|
| NAME | Jan Weckström |
| GIVEN NAMES | Jan |
| FAMILY NAME | Weckström |
| SIGNATURE | WECKSTRÖM J |
| AFFILIATIONS | University of Helsinki |
| ORCID | 0000-0001-5604-617X |
| VERIFIED | Yes |
| TOTAL WORKS | 6 |
| TOTAL CITATIONS | 7 |
| WORKS AS AUTHOR | 6 |
| WORKS AS EDITOR | 0 |
| FIRST PUBLICATION YEAR | 2000 |
| LATEST PUBLICATION YEAR | 2017 |
| H-INDEX | 1 |
Comparison of quantitative Holocene temperature reconstructions using multiple proxies from a northern boreal lake
Four biotic proxies (plant macrofossils, pollen, chironomids and diatoms) are employed to quantitatively reconstruct variations in mean July air temperatures ( T jul ) at Lake Loitsana (northern Finland) during the Holocene. The aim is to evaluate the robustness and biases in these temperature reconstructions and to compare the timing of highest T jul in the individual reconstructions. The reconstructed T jul values are evaluated in relation to l…
New evidence of warm early-Holocene summers in subarctic Finland based on an enhanced regional chironomid-based temperature calibration model
Paleoclimate reconstructions based on biological proxies present methodological challenges, especially during non-analog conditions, such as the early Holocene. Here, two chironomid-based training sets from Finland were amalgamated to create a more accurate transfer function of summer air temperature. The aim was to reconstruct Holocene paleoclimate in northernmost Lapland, in an area that has been either too warm or too cold for reliable reconst…
Chironomid response to environmental drivers during the Holocene in a shallow treeline lake in northwestern Fennoscandia
The significance of different environmental drivers for the chironomid compositional changes during the Holocene was assessed using partial redundancy analysis. These drivers included pollen-inferred mean July air temperature, vegetation cover as pollen percentages, diatom-inferred water pH and total organic carbon (TOC), and sediment properties as loss on iginition (LOI). Variance partitioning showed that on the Holocene timescale, chironomid as…
Impacts of Eutrophication on Diatom Life Forms and Species Richness in Coastal Waters of the Baltic Sea
Increased nutrient and sediment loading can affect the functioning and biodiversity of coastal ecosystems. Lacking long-term monitoring data, paleolimnological techniques enable the estimation of habitat and diversity change through time. Using these methods we assessed the effects of eutrophication on diatom community structure and species richness over the past ca. 200 years in coastal waters of the Gulf of Finland. The abundance of planktonic …
Temperature patterns over the past eight centuries in Northern Fennoscandia inferred from sedimentary diatoms
Establishing natural climate variability becomes particularly important in remote polar regions, especially when considering questions regarding higher than average warming. We present a high-resolution record of temperature variability for the past 800 yr based on sedimentary diatoms from a treeline lake in Finnish Lapland. The BSiZer multiscale smoothing technique is applied to the data to identify significant features in the record at differen…
A Quantitative Holocene Climatic Record from Diatoms in Northern Fennoscandia
A diatom-based calibration model for predicting summer temperatures was developed using climatically sensitive subarctic lakes in northern Fennoscandia. The model was applied to a sediment core from a treeline lake to infer trends in Holocene climate. The record exhibits long-term variations, as well as a series of shorter-term fluctuations on a time scale of centuries. Summers were warmest in the area about 6200 cal yr B.P. and featured distinct…
Chironomid response to environmental drivers during the Holocene in a shallow treeline lake in northwestern Fennoscandia
The significance of different environmental drivers for the chironomid compositional changes during the Holocene was assessed using partial redundancy analysis. These drivers included pollen-inferred mean July air temperature, vegetation cover as pollen percentages, diatom-inferred water pH and total organic carbon (TOC), and sediment properties as loss on iginition (LOI). Variance partitioning showed that on the Holocene timescale, chironomid as…
Comparison of quantitative Holocene temperature reconstructions using multiple proxies from a northern boreal lake
Four biotic proxies (plant macrofossils, pollen, chironomids and diatoms) are employed to quantitatively reconstruct variations in mean July air temperatures ( T jul ) at Lake Loitsana (northern Finland) during the Holocene. The aim is to evaluate the robustness and biases in these temperature reconstructions and to compare the timing of highest T jul in the individual reconstructions. The reconstructed T jul values are evaluated in relation to l…
Impacts of Eutrophication on Diatom Life Forms and Species Richness in Coastal Waters of the Baltic Sea
Increased nutrient and sediment loading can affect the functioning and biodiversity of coastal ecosystems. Lacking long-term monitoring data, paleolimnological techniques enable the estimation of habitat and diversity change through time. Using these methods we assessed the effects of eutrophication on diatom community structure and species richness over the past ca. 200 years in coastal waters of the Gulf of Finland. The abundance of planktonic …
A Quantitative Holocene Climatic Record from Diatoms in Northern Fennoscandia
A diatom-based calibration model for predicting summer temperatures was developed using climatically sensitive subarctic lakes in northern Fennoscandia. The model was applied to a sediment core from a treeline lake to infer trends in Holocene climate. The record exhibits long-term variations, as well as a series of shorter-term fluctuations on a time scale of centuries. Summers were warmest in the area about 6200 cal yr B.P. and featured distinct…
Temperature patterns over the past eight centuries in Northern Fennoscandia inferred from sedimentary diatoms
Establishing natural climate variability becomes particularly important in remote polar regions, especially when considering questions regarding higher than average warming. We present a high-resolution record of temperature variability for the past 800 yr based on sedimentary diatoms from a treeline lake in Finnish Lapland. The BSiZer multiscale smoothing technique is applied to the data to identify significant features in the record at differen…
Impacts of Eutrophication on Diatom Life Forms and Species Richness in Coastal Waters of the Baltic Sea
Increased nutrient and sediment loading can affect the functioning and biodiversity of coastal ecosystems. Lacking long-term monitoring data, paleolimnological techniques enable the estimation of habitat and diversity change through time. Using these methods we assessed the effects of eutrophication on diatom community structure and species richness over the past ca. 200 years in coastal waters of the Gulf of Finland. The abundance of planktonic …
Chironomid response to environmental drivers during the Holocene in a shallow treeline lake in northwestern Fennoscandia
The significance of different environmental drivers for the chironomid compositional changes during the Holocene was assessed using partial redundancy analysis. These drivers included pollen-inferred mean July air temperature, vegetation cover as pollen percentages, diatom-inferred water pH and total organic carbon (TOC), and sediment properties as loss on iginition (LOI). Variance partitioning showed that on the Holocene timescale, chironomid as…
New evidence of warm early-Holocene summers in subarctic Finland based on an enhanced regional chironomid-based temperature calibration model
Paleoclimate reconstructions based on biological proxies present methodological challenges, especially during non-analog conditions, such as the early Holocene. Here, two chironomid-based training sets from Finland were amalgamated to create a more accurate transfer function of summer air temperature. The aim was to reconstruct Holocene paleoclimate in northernmost Lapland, in an area that has been either too warm or too cold for reliable reconst…
Comparison of quantitative Holocene temperature reconstructions using multiple proxies from a northern boreal lake
Four biotic proxies (plant macrofossils, pollen, chironomids and diatoms) are employed to quantitatively reconstruct variations in mean July air temperatures ( T jul ) at Lake Loitsana (northern Finland) during the Holocene. The aim is to evaluate the robustness and biases in these temperature reconstructions and to compare the timing of highest T jul in the individual reconstructions. The reconstructed T jul values are evaluated in relation to l…
Geography (6 works) · Geology and Paleoclimatology Research (6 works) · Climate change (5 works) · Physical geography (5 works) · Tree-ring climate responses (5 works) · Climatology (4 works) · Geology (4 works) · Holocene (4 works) · Oceanography (4 works) · Diatom (3 works)