A century of trends in adult human height

Being taller is associated with enhanced longevity, and higher education and earnings. We reanalysed 1472 population-based studies, with measurement of height on more than 18.6 million participants to estimate mean height for people born between 1896 and 1996 in 200 countries. The largest gain in adult height over the past century has occurred in South Korean women and Iranian men, who became 20.2 cm (95% credible interval 17.5-22.7) and 16.5 cm (13.3-19.7) taller, respectively. In contrast, there was little change in adult height in some sub-Saharan African countries and in South Asia over the century of analysis. The tallest people over these 100 years are men born in the Netherlands in the last quarter of 20th century, whose average heights surpassed 182.5 cm, and the shortest were women born in Guatemala in 1896 (140.3 cm; 135.8-144.8). The height differential between the tallest and shortest populations was 19-20 cm a century ago, and has remained the same for women and increased for men a century later despite substantial changes in the ranking of countries

Increased El Nino-Southern Oscillation sensitivity of tree growth on the southern Tibetan Plateau since the 1970s

El Nino-Southern Oscillation (ENSO) affects various components of the Earth's climate systems but its role on the Tibetan Plateau remains poorly understood. Hydroclimatic changes in Asia's water tower can have substantial effects on the functioning and productivity of agricultural and natural ecosystems, and thus the wellbeing of many millions of people. Here, we use well-replicated ring-width chronologies from 10 juniper sites on the southern Tibetan Plateau to associate variations in tree growth with ENSO events between 1645 and 2001 CE. An empirical orthogonal function (EOF) was applied to emphasize regional growth coherency and climate sensitivity. May-June moisture availability was found to be most important for ring-width formation, and most growth anomalies coincided with documentary evidence of hydroclimatic extremes. The superposed epoch analysis (SEA) and the composite analysis showed an increased ENSO sensitivity in tree growth on the southern Tibetan Plateau since the 1970s, possibly due to global warming, calls for integration of large-scale ocean-atmosphere climate feedbacks into regional forest management strategies in future warming scenarios

NOAA/WDS Paleoclimatology - Western Mongolia 800 Year Summer Temperature Reconstruction

This archived Paleoclimatology Study is available from the NOAA National Centers for Environmental Information (NCEI), under the World Data Service (WDS) for Paleoclimatology. The associated NCEI study type is Climate Reconstruction. The data include parameters of climate reconstructions|tree ring with a geographic location of Mongolia, Eastern Asia. The time period coverage is from 772 to -55 in calendar years before present (BP). See metadata information for parameter and study location details. Please cite this study when using the data

NOAA/WDS Paleoclimatology - Davi - Bairam Uul/Khalzan Khamar blue intensity - LASI - ITRDB MONG043

This archived Paleoclimatology Study is available from the NOAA National Centers for Environmental Information (NCEI), under the World Data Service (WDS) for Paleoclimatology. The associated NCEI study type is Tree Ring. The data include parameters of tree ring with a geographic location of Mongolia, Eastern Asia. The time period coverage is from 772 to -55 in calendar years before present (BP). See metadata information for parameter and study location details. Please cite this study when using the data

High-resolution palaeoclimatic records for the last millennium: Interpretation, integration and comparison with General Circulation Model control-run temperatures

Palaeoclimatology provides our only means of assessing climatic variations before the beginning of instrumental records. The various proxy variables used, however, have a number of limitations which must be adequately addressed and understood. Besides their obvious spatial and seasonal limitations, different proxies are also potentially limited in their ability to represent climatic variations over a range of different timescales. Simple correlations with instrumental data over the period since AD 1881 give some guide to which are the better proxies, indicating that coral- and ice-core-based reconstructions are poorer than tree-ring and historical ones. However, the quality of many proxy time series can deteriorate during earlier times. Suggestions are made for assessing proxy quality over longer periods than the last century by intercomparing neighbouring proxies and, by comparisons with less temporally resolved proxies such as borehole temperatures. We have averaged 17 temperature reconstructions (representing various seasons of the year), all extending back at least to the mid-seventeenth century, to form two annually resolved hemispheric series (NH10 and SH7). Over the 1901-91 period, NH10 has 36% variance in common with average NH summer (June to August) temperatures and 70% on decadal timescales. SH7 has 16% variance in common with average SH summer (December to February) temperatures and 49% on decadal timescales, markedly poorer than the reconstructed NH series. The coldest year of the millennium over the NH is AD 1601, the coldest decade 1691-1700 and the seventeenth is the coldest century. A Principal Components Analysis (PCA) is performed on yearly values for the 17 reconstructions over the period AD 1660-1970. The correlation between PC1 and NH10 is 0.92, even though PC1 explains only 13.6% of the total variance of all 17 series. Similar PCA is performed on thousand-year-long General Circulation Model (GCM) data from the Geophysical Fluid Dynamics Laboratory (GFDL) and the Hadley Centre (HADCM2), sampling these for the same locations and seasons as the proxy data. For GFDL, the correlation between its PC1 and its NH10 is 0,89, while for HADCM2 the PCs group markedly differently. Cross-spectral analyses are performed on the proxy data and the GFDL model data at two different frequency bands (0.02 and 0.03 cycles per year). Both analyses suggest that there is no large-scale coherency in the series on these timescales. This implies that if the proxy data are meaningful, it should be relatively straightforward to detect a coherent near-global anthropogenic signal in surface temperature data