Contributions to a meteorology of the Tibetan highlands

August 1968.Includes bibliographical references.Sponsored by the National Environmental Satellite Center, ESSA E-10-68G

Life on a Warmer Earth - Possible Climatic Consequences of Man-Made Global Warming

An IIASA Executive Report based on and IIASA research report by H. Flohn, who has taken a paleoclimatic approach to gaining insights into the implications of global warming produced by he burning of fossil fuels. Using the most reliable radiation models for the relation between carbon dioxide content of the atmosphere and temperature, Flohn selects thresholds of temperature increase, which he then speculates would produce climatic conditions similar to those of earlier periods in the earth's history. He establishes a four-part scenario. An increase in the global average surface temperature (GAST) of 1 degree C, which could occur around 2000-2010 at the projected rate of fossil fuel consumption, would correspond to the GAST 1,000 years ago during the early middle ages. Warming of 1.5 degrees C could occur around 2005-2030, mimicking conditions 6000 years ago at the peak of the Holocene period. Warming of 2.5 degrees C is considered possible around 2020-2050, corresponding to the last interglacial period 120,000 years ago. Finally, an increase of the GAST by 4 degrees C could be reached 2040-2080, producing conditions that occurred during the late Tertiary Period from 2.5 to 12 million years ago, a remarkable epoch when the North Pole became ice free while the South Pole remained glaciated. The Executive Report briefly describe what is known and generally assumed about the climate of the earth during each of the four periods

Possible Climatic Consequences of a Man-Made Global Warming

There is increasing concern about man's impact on climate. Studying this problem one comes to realize that this influence is not so much felt as a variation of the average values of global climate, such as temperature and pressure. Of concern is instead a change in the climatological patterns, with the average values changing very little. Actually this could be a change in rainfall patterns, for example. Among other effects, increasing levels of carbon dioxide could cause a man-made global warming. While it is impossible to determine such changes in climate patterns given the present state of the art, we consider it perhaps useful to study the changes that occurred in the climate patterns of the past. Today's highly sophisticated knowledge in paleometeorology allows to undertake such a venture -- a research activity that may also be crucial for our understanding of the forthcoming CO2 problem

Ein geophysikalisches Eiszeit-Modell

Auf der Grundlage der jüngsten Fortschritte in vielen Zweigen der Geophysik — Glaziologie, Meteorologie, Ozeanographie, Paläomagnetismus und Tektonophysik — wird ein synthetisches, rein geophysikalisches Modell der Klimaentwicklung im Tertiär und Pleistozän (mit Ausblicken auf das Permokarbon) entwickelt. Hierbei wird besonderes Gewicht auf die Abschätzung des Wärmehaushaltes der Ozeane gelegt; extraterrestrische Faktoren liefern höchstens einen sekundären Beitrag. Als Unterlage für eine weitere Diskussion wird eine knappe Zusammenstellung der wesentlichen Gesichtspunkte in Form von 10 Sätzen (Kapitel 6) gegeben.researc

Zur meteorologischen Interpretation der pleistozänen Klimaschwankungen

Einige allgemeine Fragen der pleistozänen Klimaschwankungen werden vom meteorologischen Standpunkt aus erörtert, unter besonderer Berücksichtigung des Massen- und Wärmehaushalts. Hierzu gehören das Auftreten alternierender Pluviale von entweder tropischer oder polarer Herkunft, von denen nur die letzteren mit den Eiszeiten synchronisieren, die Deutung des allmählichen Absinkens der interglazialen Meeresstände als Folge des graduellen Aufbaus des antarktischen Inlandeises seit Beginn des Pleistozäns, die Diskussion der meteorologischen Verhältnisse während der postglazialen Abschmelzperiode der kontinentalen Inlandeismassen.researc

Tibet, the Himalaya, Asian monsoons and biodiversity - In what ways are they related?

Prevailing dogma asserts that the uplift of Tibet, the onset of the Asian monsoon system and high biodiversity in southern Asia are linked, and that all occurred after 23 million years ago in the Neogene. Here, spanning the last 60 million years of Earth history, the geological, climatological and palaeontological evidence for this linkage is reviewed. The principal conclusions are that: 1) A proto-Tibetan highland existed well before the Neogene and that an Andean type topography with surface elevations of at least 4.5 km existed at the start of the Eocene, before final closure of the Tethys Ocean that separated India from Eurasia. 2) The Himalaya were formed not at the start of the India-Eurasia collision, but after much of Tibet had achieved its present elevation. The Himalaya built against a pre-existing proto-Tibetan highland and only projected above the average height of the plateau after approximately 15 Ma. 3) Monsoon climates have existed across southern Asia for the whole of the Cenozoic, and probably for a lot longer, but that they were of the kind generated by seasonal migrations of the Inter-tropical Convergence Zone. 4) The projection of the High Himalaya above the Tibetan Plateau at about 15 Ma coincides with the development of the modern South Asia Monsoon. 5) The East Asia monsoon became established in its present form about the same time as a consequence of topographic changes in northern Tibet and elsewhere in Asia, the loss of moisture sources in the Asian interior and the development of a strong winter Siberian high as global temperatures declined. 6) New radiometric dates of palaeontological finds point to southern Asia's high biodiversity originating in the Paleogene, not the Neogene

Cenozoic evolution of Asian climate and sources of Pacific seawater Pb and Nd derived from eolian dust of sediment core LL44‐GPC3

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95692/1/palo954.pd

The extratropical upper troposphere and lower stratosphere

The extratropical upper troposphere and lower stratosphere (Ex-UTLS) is a transition region between the stratosphere and the troposphere. The Ex-UTLS includes the tropopause, a strong static stability gradient and dynamic barrier to transport. The barrier is reflected in tracer profiles. This region exhibits complex dynamical, radiative, and chemical characteristics that place stringent spatial and temporal requirements on observing and modeling systems. The Ex-UTLS couples the stratosphere to the troposphere through chemical constituent transport (of, e.g., ozone), by dynamically linking the stratospheric circulation with tropospheric wave patterns, and via radiative processes tied to optically thick clouds and clear-sky gradients of radiatively active gases. A comprehensive picture of the Ex-UTLS is presented that brings together different definitions of the tropopause, focusing on observed dynamical and chemical structure and their coupling. This integral view recognizes that thermal gradients and dynamic barriers are necessarily linked, that these barriers inhibit mixing and give rise to specific trace gas distributions, and that there are radiative feedbacks that help maintain this structure. The impacts of 21st century anthropogenic changes to the atmosphere due to ozone recovery and climate change will be felt in the Ex-UTLS, and recent simulations of these effects are summarized and placed in context

Influence of the Tibetan Plateau uplift on the Asian monsoon-arid environment evolution

As one of the most important geological events in Cenozoic era, the uplift of the Tibetan Plateau (TP) has had profound influences on the Asian and global climate and environment evolution. During the past four decades, many scholars from China and abroad have studied climatic and environmental effects of the TP uplift by using a variety of geological records and paleoclimate numerical simulations. The existing research results enrich our understanding of the mechanisms of Asian monsoon changes and interior aridification, but so far there are still a lot of issues that need to be thought deeply and investigated further. This paper attempts to review the research on the influence of the TP uplift on the Asian monsoon-arid environment, summarize three types of numerical simulations including bulk-plateau uplift, phased uplift and sub-regional uplift, and especially to analyze regional differences in responses of climate and environment to different forms of tectonic uplifts. From previous modeling results, the land-sea distribution and the Himalayan uplift may have a large effect in the establishment and development of the South Asian monsoon. However, the formation and evolution of the monsoon in northern East Asia, the intensified dryness north of the TP and enhanced Asian dust cycle may be more closely related to the uplift of the main body, especially the northern part of the TP. In this review, we also discuss relative roles of the TP uplift and other impact factors, origins of the South Asian monsoon and East Asian monsoon, feedback effects and nonlinear responses of climatic and environmental changes to the plateau uplift. Finally, we make comparisons between numerical simulations and geological records, discuss their uncertainties, and highlight some problems worthy of further studying