Wallace S Broecker
Datos Biográficos
| ID | 4455508 |
|---|---|
| NOMBRE | Wallace S Broecker |
| NOMBRES | Wallace S |
| APELLIDO | Broecker |
| FIRMA | BROECKER W S |
| AFILIACIONES | Lamont-Doherty Earth Observatory |
| ORCID | 0000-0003-4816-0903 |
| VERIFICADO | Sí |
| TOTAL DE OBRAS | 29 |
| TOTAL DE CITAS | 136 |
| TOTAL COMO AUTOR | 29 |
| TOTAL COMO EDITOR | 0 |
| PRIMER AÑO DE PUBLICACIÓN | 1956 |
| AÑO MÁS RECIENTE DE PUBLICACIÓN | 2021 |
| ÍNDICE H | 5 |
Rock varnish record of the African Humid Period in the Lake Turkana basin of East Africa
Rock varnish is a manganiferous dark coating accreted on subaerially exposed rocks in drylands. It often contains a layered microstratigraphy that records past wetness variations. Varnish samples from latest Pleistocene and Holocene geomorphic features in the Lake Turkana basin, East Africa display a regionally replicable microstratigraphy record of Holocene millennial-scale wetness variability and a broad interval of wetter conditions during the…
How to Build a Habitable Planet
Chronostratigraphy and lake-level changes of Laguna Cari-Laufquén, Río Negro, Argentina
Evidence from shoreline and deep-lake sediments show Laguna Cari-Laufquén, located at 41°S in central Argentina, rose and fell repeatedly during the late Quaternary. Our results show that a deep (> 38 m above modern lake level) lake persisted from no later than 28 ka to 19 ka, with the deepest lake phase from 27 to 22 ka. No evidence of highstands is found after 19 ka until the lake rose briefly in the last millennia to 12 m above the modern lake…
Last Interglacial Climates
The last interglacial, commonly understood as an interval with climate as warm or warmer than today, is represented by marine isotope stage (MIS) 5e, which is a proxy record of low global ice volume and high sea level. It is arbitrarily dated to begin at approximately 130,000 yr B.P. and end at 116,000 yr B.P. with the onset of the early glacial unit MIS 5d. The age of the stage is determined by correlation to uranium–thorium dates of raised cora…
Was the Medieval Warm Period Global?
During the Medieval Warm Period (800 to 1200 A.D.), the Vikings colonized Greenland. In his Perspective, Broecker discusses whether this warm period was global or regional in extent. He argues that it is the last in a long series of climate fluctuations in the North Atlantic, that it was likely global, and that the present warming should be attributed in part to such an oscillation, upon which the warming due to greenhouse gases is superimposed.
A Reassessment of U-Th and 14 C Ages for Late-Glacial High-Frequency Hydrological Events at Searles Lake, California
U-Th isochron ages of tufas formed on shorelines suggest that the last pluvial event in Lake Lahontan and Searles Lake was synchronous at about 16,500 cal yr B.P. (equivalent to a radiocarbon age of between 14,000 and 13,500 yr B.P.), whereas the timing of this pluvial event determined by radiocarbon dating is on the order of 1000 yr younger. The timing of seven distinct periods of near desiccation in Searles Lake during late-glacial time has bee…
Antiphasing between Rainfall in Africa's Rift Valley and North America's Great Basin
The beginning of the Bølling-Allerød warm period was marked in Greenland ice by an abrupt rise in δ 18 O, an abrupt drop in dust rain, and an abrupt increase in atmospheric methane content. The surface waters in the Norwegian Sea underwent a simultaneous abrupt warming. At about this time, a major change in the pattern of global rainfall occurred. Lake Victoria (latitude 0°), which prior to this time was dry, was rejuvenated. The Red Sea, which p…
Transect Along 24°n Latitude of 14 C in Dissolved Inorganic Carbon in the Subtropical North Atlantic Ocean
The distribution of bomb-produced 14 C in the ocean provides a powerful constraint for circulation models of upper ocean mixing. We report 14 C measurements from an east-west section of the main thermocline at 24°N latitude in the subtropical North Atlantic Ocean in summer 1992, and one profile from the Gulf of Mexico in 1993. Observed gradients reflect the transient invasion of bomb 14 C into the thermocline via mixing along isopycnals from the …
The Effect of Tillage on Soil Organic Matter Using 14 C
We compared four adjacent soil plots in an effort to determine the effect of land use on soil carbon storage. The plots were located at the High Plains Agricultural Research Laboratory near Sidney, Nebraska. We measured 14 C, total carbon, total nitrogen and 137 Ce to determine the size and turnover times of rapid and stable soil organic matter (SOM) pools, and their relation to land-use practices. Results were consistent with the model produced …
A 30,000 yr Continental Paleotemperature Record Derived from Noble Gases Dissolved in Groundwater from the San Juan Basin, New Mexico
Paleotemperatures for the last glacial maximum (LGM) have been derived from noble gases dissolved in 14 C-dated groundwater of the Ojo Alamo and the Nacimiento formations in the San Juan Basin, northwestern New Mexico. The difference in mean annual (ground) temperature between the Holocene and the LGM was determined to be 5.5 ± 0.7°C. A practically identical result, 5.2 ± 0.7°C, has been obtained previously from the Carrizo aquifer in southern Te…
Correlations between climate records from North Atlantic sediments and Greenland ice
Defining the Boundaries of the Late-Glacial Isotope Episodes
Evidence for massive discharges of icebergs into the North Atlantic ocean during the last glacial period
Accelerator Mass Spectrometric Radiocarbon Measurements on Foraminifera Shells from Deep-Sea Cores
Radiocarbon ages determined by the AMS method on hand-picked foraminifera shells are reported. The results allow estimates of the ventilation rate of the deep Atlantic and Pacific Oceans during glacial time. They also extend our knowledge of the chronology of events associated with the transition from full glacial conditions ca 15,000 years ago to full interglacial conditions ca 8000 years ago. This and the previous lists (Broecker et al 1988c) c…
Anomalous AMS Radiocarbon Ages for Foraminifera from High-Deposition-Rate Ocean Sediments
Radiocarbon ages on handpicked foraminifera from deep-sea cores are revealing that areas of rapid sediment accumulation are in some cases subject to hiatuses, reworking and perhaps secondary calcite deposition. We present here an extreme example of the impacts of such disturbances. The message is that if precise chronologies or meaningful benthic planktic age differences are to be obtained, then it is essential to document the reliability of radi…
Can the Greenland Climatic Jumps be Identified in Records from Ocean and Land?
Sharp jumps in climate punctuate the records from borings in the Greenland ice cap during the time interval 60,000 to about 20,000 yr ago. Rapid fluctuations are also seen in foraminifera records for cores from the northern Atlantic and in a pollen record from a core from a bog in the Vosges Mountains in France. In this paper we present a new radiocarbon chronology for northern Atlantic deep-sea core V23-81 which permits comparison with the radio…
Oxygen Isotope Constraints on Surface Ocean Temperatures
Published oxygen isotope results from benthic and planktonic foraminifera are used to constrain the extent to which surface ocean temperatures in the tropics changed between glacial and interglacial time. The possible impacts of bioturbation and of the redistribution of 18 O/ 16 O ratios within the sea, putting aside the oxygen isotope results, are consistent with the CLIMAP project conclusion that tropical ocean temperatures remained within ±2°C…
Carbon Cycle
The hottest topic for those interested in the earth's carbon cycles is the change in atmospheric CO 2 content between glacial and interglacial time. What caused it? What is its role in glacial cycles? We evaluate here the hypotheses that have been put forward to explain the CO 2 change with evidence from deep sea sediments. We conclude that all the hypotheses have serious drawbacks and that much effort will have to be expended in gathering more d…
Dating Indian Corals by U-Decay-Series Methods
Nine samples of corals collected from seven locations in the Saurashtra Coastal region of India were dated by 238 U series disequilibrium methods. Of the three age groups (6000, 30,000, and 120,000 yr) reported for this region by the earlier studies of S. K. Gupta and B. S. Amin (1974, Marine Geology 16, 79–83), we could confirm only the 6000-yr group. Instead of a 120,000-yr group, we found a scatter of ages between 118,000 and 176,000 yr. There…
Modeling the Carbon System
Claims that forest cutting during the last few decades has contributed significantly to the buildup in atmospheric CO 2 have cast doubt on the validity of models used to estimate CO 2 uptake by the ocean. In this paper we review the existing models and conclude that the box-diffusion model of Oeschger and his co-workers provides an excellent fit to the average distributions of natural and bomb-produced radiocarbon. We also take the first steps to…
Rates of Benthic Mixing in Deep-Sea Sediment as Determined by Radioactive Tracers
A series of closely spaced radiocarbon measurements on a carbonate-rich box core from the western equatorial Pacific show a mixed layer at least 7 cm thick, with 14 C ages between 4000 and 5000 years, and an orderly progression of ages below this layer, indicating an average sedimentation rate of about 2 cm/10 3 yr. The profile can be simulated using a numerical extension of the mixing model of Guinasso and Schink (1975) and a numerical exponenti…
A Direct Comparison of 14 C and 230 Th Ages at Searles Lake, California
Thorium-230 dating on saline of the Lower Salt unit in pluvial Searles Lake, California, shows that this unit was formed between 24,500 and 32,000 years ago. The initial apparent 14 C age of the lake is estimated to be about 900 years. After correcting for nonradiogenic 230 Th and for the initial 14 C age, excellent agreement between 230 Th and 14 C ages is obtained. The reliability of 230 Th dating on salt deposit opens a new way for continuatio…
Quaternary Sea Level Fluctuations on a Tectonic coast
Emerged coral reef terraces on the Huon Peninsula in New Guinea were reported in a reconnaissance dating study by Veeh and Chappell 1970. Age definition achieved was not good for several important terraces, and we report here a series of new 230 Th/ 234 U dates, which further clarify the history of late Quaternary eustatic sea level fluctuations. More than 20 reef complexes are present, ranging well beyond 250,000 yr old: we are concerned with th…
A Kinetic Model for the Chemical Composition of Sea Water
The thermodynamic ocean of the Sillen school offers little incentive to those who search the sedimentary record for evidence of changes in ocean chemistry during Cenozoic time. Their models predict a uniform chemical composition. However as the sediments presently accumulating in the ocean show little evidence of equilibration with the overlying water, the possibility that kinetic factors play an important role must be seriously explored. Such a …
Lamont Radiocarbon Measurements VIII
Like Lamont VI (Broecker and Olson, 1959), this list contains only results on samples of known age (most of which formed during the past ten years). The measurements were made largely in order to gain an understanding of the distribution of radiocarbon within the dynamic carbon reservoir. Again, the data are not reported primarily with the idea of drawing new conclusions but rather to bring together in one place information which is presently sca…
Lamont Radiocarbon Measurements VIII
Like Lamont VI (Broecker and Olson, 1959), this list contains only results on samples of known age (most of which formed during the past ten years). The measurements were made largely in order to gain an understanding of the distribution of radiocarbon within the dynamic carbon reservoir. Again, the data are not reported primarily with the idea of drawing new conclusions but rather to bring together in one place information which is presently sca…
Lamont Natural Radiocarbon Measurements VII
Radiocarbon-age measurements reported here were made at Lamont Geological Observatory between July 1958 and November 1960. Sample descriptions are classified as follows: I. Samples associated with glacial deposits II. Samples associated with marine coastal deposits III. Samples associated with marine coastal deposits uplifted by glacial rebound IV. Samples associated with pluvial-lake deposits V. Samples from deep-sea cores VI. Samples from cave …
Lamont Radiocarbon Measurements VI
In contrast to previous radiocarbon measurement lists, this list contains only known-age samples, most of which formed during the past ten years. The measurements were made largely in order to gain an understanding of the distribution of radiocarbon within the dynamic carbon reservoir both today and at times in the past. Since all materials forming in this reservoir today do not have the same C 14 /C 12 ratio, such an understanding is necessary i…
Modeling the Carbon System
Claims that forest cutting during the last few decades has contributed significantly to the buildup in atmospheric CO 2 have cast doubt on the validity of models used to estimate CO 2 uptake by the ocean. In this paper we review the existing models and conclude that the box-diffusion model of Oeschger and his co-workers provides an excellent fit to the average distributions of natural and bomb-produced radiocarbon. We also take the first steps to…
The Radiocarbon Method of Age Determination
Five years after the first publication of age measurements by the radiocarbon method (Arnold and Libby 1951) the method has been established as a powerful technique in the study of archaeology. Lists of radiocarbon dates have been published by a number of laboratories (Libby 1951, 1952, 1954, 1955; Kulp 1951, 1952; Broecker and Kulp 1956; Suess 1954; Ruben and Suess 1955; Blau, Deevey, and Gross 1953; Preston, Person, and Deevey 1955; Ralph 1955;…
Accelerator Mass Spectrometric Radiocarbon Measurements on Foraminifera Shells from Deep-Sea Cores
Radiocarbon ages determined by the AMS method on hand-picked foraminifera shells are reported. The results allow estimates of the ventilation rate of the deep Atlantic and Pacific Oceans during glacial time. They also extend our knowledge of the chronology of events associated with the transition from full glacial conditions ca 15,000 years ago to full interglacial conditions ca 8000 years ago. This and the previous lists (Broecker et al 1988c) c…
The Effect of Tillage on Soil Organic Matter Using 14 C
We compared four adjacent soil plots in an effort to determine the effect of land use on soil carbon storage. The plots were located at the High Plains Agricultural Research Laboratory near Sidney, Nebraska. We measured 14 C, total carbon, total nitrogen and 137 Ce to determine the size and turnover times of rapid and stable soil organic matter (SOM) pools, and their relation to land-use practices. Results were consistent with the model produced …
Anomalous AMS Radiocarbon Ages for Foraminifera from High-Deposition-Rate Ocean Sediments
Radiocarbon ages on handpicked foraminifera from deep-sea cores are revealing that areas of rapid sediment accumulation are in some cases subject to hiatuses, reworking and perhaps secondary calcite deposition. We present here an extreme example of the impacts of such disturbances. The message is that if precise chronologies or meaningful benthic planktic age differences are to be obtained, then it is essential to document the reliability of radi…
Rock varnish record of the African Humid Period in the Lake Turkana basin of East Africa
Rock varnish is a manganiferous dark coating accreted on subaerially exposed rocks in drylands. It often contains a layered microstratigraphy that records past wetness variations. Varnish samples from latest Pleistocene and Holocene geomorphic features in the Lake Turkana basin, East Africa display a regionally replicable microstratigraphy record of Holocene millennial-scale wetness variability and a broad interval of wetter conditions during the…
Transect Along 24°n Latitude of 14 C in Dissolved Inorganic Carbon in the Subtropical North Atlantic Ocean
The distribution of bomb-produced 14 C in the ocean provides a powerful constraint for circulation models of upper ocean mixing. We report 14 C measurements from an east-west section of the main thermocline at 24°N latitude in the subtropical North Atlantic Ocean in summer 1992, and one profile from the Gulf of Mexico in 1993. Observed gradients reflect the transient invasion of bomb 14 C into the thermocline via mixing along isopycnals from the …
Carbon Cycle
The hottest topic for those interested in the earth's carbon cycles is the change in atmospheric CO 2 content between glacial and interglacial time. What caused it? What is its role in glacial cycles? We evaluate here the hypotheses that have been put forward to explain the CO 2 change with evidence from deep sea sediments. We conclude that all the hypotheses have serious drawbacks and that much effort will have to be expended in gathering more d…
The Radiocarbon Method of Age Determination
Five years after the first publication of age measurements by the radiocarbon method (Arnold and Libby 1951) the method has been established as a powerful technique in the study of archaeology. Lists of radiocarbon dates have been published by a number of laboratories (Libby 1951, 1952, 1954, 1955; Kulp 1951, 1952; Broecker and Kulp 1956; Suess 1954; Ruben and Suess 1955; Blau, Deevey, and Gross 1953; Preston, Person, and Deevey 1955; Ralph 1955;…
The geochemistry of C14 in fresh-water systems
Lamont Radiocarbon Measurements VI
In contrast to previous radiocarbon measurement lists, this list contains only known-age samples, most of which formed during the past ten years. The measurements were made largely in order to gain an understanding of the distribution of radiocarbon within the dynamic carbon reservoir both today and at times in the past. Since all materials forming in this reservoir today do not have the same C 14 /C 12 ratio, such an understanding is necessary i…
Lamont Radiocarbon Measurements VIII
Like Lamont VI (Broecker and Olson, 1959), this list contains only results on samples of known age (most of which formed during the past ten years). The measurements were made largely in order to gain an understanding of the distribution of radiocarbon within the dynamic carbon reservoir. Again, the data are not reported primarily with the idea of drawing new conclusions but rather to bring together in one place information which is presently sca…
Lamont Natural Radiocarbon Measurements VII
Radiocarbon-age measurements reported here were made at Lamont Geological Observatory between July 1958 and November 1960. Sample descriptions are classified as follows: I. Samples associated with glacial deposits II. Samples associated with marine coastal deposits III. Samples associated with marine coastal deposits uplifted by glacial rebound IV. Samples associated with pluvial-lake deposits V. Samples from deep-sea cores VI. Samples from cave …
A Kinetic Model for the Chemical Composition of Sea Water
The thermodynamic ocean of the Sillen school offers little incentive to those who search the sedimentary record for evidence of changes in ocean chemistry during Cenozoic time. Their models predict a uniform chemical composition. However as the sediments presently accumulating in the ocean show little evidence of equilibration with the overlying water, the possibility that kinetic factors play an important role must be seriously explored. Such a …
Quaternary Sea Level Fluctuations on a Tectonic coast
Emerged coral reef terraces on the Huon Peninsula in New Guinea were reported in a reconnaissance dating study by Veeh and Chappell 1970. Age definition achieved was not good for several important terraces, and we report here a series of new 230 Th/ 234 U dates, which further clarify the history of late Quaternary eustatic sea level fluctuations. More than 20 reef complexes are present, ranging well beyond 250,000 yr old: we are concerned with th…
A Direct Comparison of 14 C and 230 Th Ages at Searles Lake, California
Thorium-230 dating on saline of the Lower Salt unit in pluvial Searles Lake, California, shows that this unit was formed between 24,500 and 32,000 years ago. The initial apparent 14 C age of the lake is estimated to be about 900 years. After correcting for nonradiogenic 230 Th and for the initial 14 C age, excellent agreement between 230 Th and 14 C ages is obtained. The reliability of 230 Th dating on salt deposit opens a new way for continuatio…
Rates of Benthic Mixing in Deep-Sea Sediment as Determined by Radioactive Tracers
A series of closely spaced radiocarbon measurements on a carbonate-rich box core from the western equatorial Pacific show a mixed layer at least 7 cm thick, with 14 C ages between 4000 and 5000 years, and an orderly progression of ages below this layer, indicating an average sedimentation rate of about 2 cm/10 3 yr. The profile can be simulated using a numerical extension of the mixing model of Guinasso and Schink (1975) and a numerical exponenti…
Modeling the Carbon System
Claims that forest cutting during the last few decades has contributed significantly to the buildup in atmospheric CO 2 have cast doubt on the validity of models used to estimate CO 2 uptake by the ocean. In this paper we review the existing models and conclude that the box-diffusion model of Oeschger and his co-workers provides an excellent fit to the average distributions of natural and bomb-produced radiocarbon. We also take the first steps to…
Dating Indian Corals by U-Decay-Series Methods
Nine samples of corals collected from seven locations in the Saurashtra Coastal region of India were dated by 238 U series disequilibrium methods. Of the three age groups (6000, 30,000, and 120,000 yr) reported for this region by the earlier studies of S. K. Gupta and B. S. Amin (1974, Marine Geology 16, 79–83), we could confirm only the 6000-yr group. Instead of a 120,000-yr group, we found a scatter of ages between 118,000 and 176,000 yr. There…
Oxygen Isotope Constraints on Surface Ocean Temperatures
Published oxygen isotope results from benthic and planktonic foraminifera are used to constrain the extent to which surface ocean temperatures in the tropics changed between glacial and interglacial time. The possible impacts of bioturbation and of the redistribution of 18 O/ 16 O ratios within the sea, putting aside the oxygen isotope results, are consistent with the CLIMAP project conclusion that tropical ocean temperatures remained within ±2°C…
Carbon Cycle
The hottest topic for those interested in the earth's carbon cycles is the change in atmospheric CO 2 content between glacial and interglacial time. What caused it? What is its role in glacial cycles? We evaluate here the hypotheses that have been put forward to explain the CO 2 change with evidence from deep sea sediments. We conclude that all the hypotheses have serious drawbacks and that much effort will have to be expended in gathering more d…
Can the Greenland Climatic Jumps be Identified in Records from Ocean and Land?
Sharp jumps in climate punctuate the records from borings in the Greenland ice cap during the time interval 60,000 to about 20,000 yr ago. Rapid fluctuations are also seen in foraminifera records for cores from the northern Atlantic and in a pollen record from a core from a bog in the Vosges Mountains in France. In this paper we present a new radiocarbon chronology for northern Atlantic deep-sea core V23-81 which permits comparison with the radio…
Anomalous AMS Radiocarbon Ages for Foraminifera from High-Deposition-Rate Ocean Sediments
Radiocarbon ages on handpicked foraminifera from deep-sea cores are revealing that areas of rapid sediment accumulation are in some cases subject to hiatuses, reworking and perhaps secondary calcite deposition. We present here an extreme example of the impacts of such disturbances. The message is that if precise chronologies or meaningful benthic planktic age differences are to be obtained, then it is essential to document the reliability of radi…
Accelerator Mass Spectrometric Radiocarbon Measurements on Foraminifera Shells from Deep-Sea Cores
Radiocarbon ages determined by the AMS method on hand-picked foraminifera shells are reported. The results allow estimates of the ventilation rate of the deep Atlantic and Pacific Oceans during glacial time. They also extend our knowledge of the chronology of events associated with the transition from full glacial conditions ca 15,000 years ago to full interglacial conditions ca 8000 years ago. This and the previous lists (Broecker et al 1988c) c…
Defining the Boundaries of the Late-Glacial Isotope Episodes
Evidence for massive discharges of icebergs into the North Atlantic ocean during the last glacial period
Correlations between climate records from North Atlantic sediments and Greenland ice
A 30,000 yr Continental Paleotemperature Record Derived from Noble Gases Dissolved in Groundwater from the San Juan Basin, New Mexico
Paleotemperatures for the last glacial maximum (LGM) have been derived from noble gases dissolved in 14 C-dated groundwater of the Ojo Alamo and the Nacimiento formations in the San Juan Basin, northwestern New Mexico. The difference in mean annual (ground) temperature between the Holocene and the LGM was determined to be 5.5 ± 0.7°C. A practically identical result, 5.2 ± 0.7°C, has been obtained previously from the Carrizo aquifer in southern Te…
Transect Along 24°n Latitude of 14 C in Dissolved Inorganic Carbon in the Subtropical North Atlantic Ocean
The distribution of bomb-produced 14 C in the ocean provides a powerful constraint for circulation models of upper ocean mixing. We report 14 C measurements from an east-west section of the main thermocline at 24°N latitude in the subtropical North Atlantic Ocean in summer 1992, and one profile from the Gulf of Mexico in 1993. Observed gradients reflect the transient invasion of bomb 14 C into the thermocline via mixing along isopycnals from the …
The Effect of Tillage on Soil Organic Matter Using 14 C
We compared four adjacent soil plots in an effort to determine the effect of land use on soil carbon storage. The plots were located at the High Plains Agricultural Research Laboratory near Sidney, Nebraska. We measured 14 C, total carbon, total nitrogen and 137 Ce to determine the size and turnover times of rapid and stable soil organic matter (SOM) pools, and their relation to land-use practices. Results were consistent with the model produced …
A Reassessment of U-Th and 14 C Ages for Late-Glacial High-Frequency Hydrological Events at Searles Lake, California
U-Th isochron ages of tufas formed on shorelines suggest that the last pluvial event in Lake Lahontan and Searles Lake was synchronous at about 16,500 cal yr B.P. (equivalent to a radiocarbon age of between 14,000 and 13,500 yr B.P.), whereas the timing of this pluvial event determined by radiocarbon dating is on the order of 1000 yr younger. The timing of seven distinct periods of near desiccation in Searles Lake during late-glacial time has bee…
Antiphasing between Rainfall in Africa's Rift Valley and North America's Great Basin
The beginning of the Bølling-Allerød warm period was marked in Greenland ice by an abrupt rise in δ 18 O, an abrupt drop in dust rain, and an abrupt increase in atmospheric methane content. The surface waters in the Norwegian Sea underwent a simultaneous abrupt warming. At about this time, a major change in the pattern of global rainfall occurred. Lake Victoria (latitude 0°), which prior to this time was dry, was rejuvenated. The Red Sea, which p…
Was the Medieval Warm Period Global?
During the Medieval Warm Period (800 to 1200 A.D.), the Vikings colonized Greenland. In his Perspective, Broecker discusses whether this warm period was global or regional in extent. He argues that it is the last in a long series of climate fluctuations in the North Atlantic, that it was likely global, and that the present warming should be attributed in part to such an oscillation, upon which the warming due to greenhouse gases is superimposed.
Geology and Paleoclimatology Research (22 obras) · Geology (17 obras) · Radiocarbon dating (13 obras) · Oceanography (12 obras) · Paleontology (12 obras) · Geography (11 obras) · Geology (11 obras) · Climatology (9 obras) · Glacial period (9 obras) · Paleontology (9 obras)