DOUGLASS ON CLIMATIC CYCLES AND TREE-GROWTH1

Discovery of the 5.7-Year Douglass Cycle: A Pioneer’s Quest for Solar Cycles in Tree-Ring Records

The astronomer A.E. Douglass is generally recognized as the founding father of dendrochronology. He studied tree rings in the search for evidence that solar variation (as seen in sunspots) is reflected in climate variation. He was convinced that his quest was successful. Analysis of some of his early data using Fourier decomposition and comparison of tree-ring periodograms with those based on k...

Generalized Milankovitch Cycles and Longterm Climatic Habitability

Although the Earth’s orbit is never far from circular, terrestrial planets around other stars might experience substantial changes in eccentricity. Eccentricity variations could lead to climate changes, including possible “phase transitions” such as the snowball transition (or its opposite). There is evidence that Earth has gone through at least one globally frozen, “snowball” state in the last...

Geophysics: J. C. Merriam Symposium on Climatic Cycles

Complementarity effects on tree growth are contingent on tree size and climatic conditions across Europe

Neglecting tree size and stand structure dynamics might bias the interpretation of the diversity-productivity relationship in forests. Here we show evidence that complementarity is contingent on tree size across large-scale climatic gradients in Europe. We compiled growth data of the 14 most dominant tree species in 32,628 permanent plots covering boreal, temperate and Mediterranean forest biom...

Balanced growth1

Balanced growth has at least two different meanings in economics. In macroeconomics, balanced growth occurs when output and the capital stock grow at the same rate. This growth path can rationalize the long-run stability of real interest rates, but its existence requires strong assumptions. In development economics, balanced growth refers to the simultaneous, coordinated expansion of several se...