Evolution of the stratospheric aerosol in the northern hemisphere following the June 1991 volcanic eruption of Mount Pinatubo: Role of tropospheric-stratospheric exchange and transport

1996 ◽  
Vol 101 (D1) ◽  
pp. 1553-1570 ◽  
Author(s):  
Hafliòi H. Jónsson ◽  
James C. Wilson ◽  
Charles A. Brock ◽  
J. E. Dye ◽  
G. V. Ferry ◽  
...  
Keyword(s):  
Northern Hemisphere ◽  
Volcanic Eruption ◽  
Stratospheric Aerosol ◽  
Mount Pinatubo

Processes of long-term relaxation of stratospheric aerosol layer in Northern Hemisphere midlatitudes after a powerful volcanic eruption

2001 ◽  
Vol 35 (30) ◽  
pp. 5059-5066 ◽  
Author(s):  
V.V Zuev ◽  
V.D Burlakov ◽  
A.V El’nikov ◽  
A.P Ivanov ◽  
A.P Chaikovskii ◽  
...  
Keyword(s):  
Northern Hemisphere ◽  
Volcanic Eruption ◽  
Stratospheric Aerosol ◽  
Aerosol Layer

Alpha-Effect, Current and Kinetic Helicities for Magnetically Driven Turbulence, and Solar Dynamo

2000 ◽  
Vol 179 ◽  
pp. 387-388
Author(s):  
Gaetano Belvedere ◽  
V. V. Pipin ◽  
G. Rüdiger
Keyword(s):  
Southern Hemisphere ◽  
Northern Hemisphere ◽  
Convection Zone ◽  
Solar Surface ◽  
Momentum Transport ◽  
Angular Momentum Transport ◽  
Magnetic Buoyancy ◽  
Alpha Effect ◽  
Current Helicity

Extended AbstractRecent numerical simulations lead to the result that turbulence is much more magnetically driven than believed. In particular the role ofmagnetic buoyancyappears quite important for the generation ofα-effect and angular momentum transport (Brandenburg & Schmitt 1998). We present results obtained for a turbulence field driven by a (given) Lorentz force in a non-stratified but rotating convection zone. The main result confirms the numerical findings of Brandenburg & Schmitt that in the northern hemisphere theα-effect and the kinetic helicityℋkin= 〈u′ · rotu′〉 are positive (and negative in the northern hemisphere), this being just opposite to what occurs for the current helicityℋcurr= 〈j′ ·B′〉, which is negative in the northern hemisphere (and positive in the southern hemisphere). There has been an increasing number of papers presenting observations of current helicity at the solar surface, all showing that it isnegativein the northern hemisphere and positive in the southern hemisphere (see Rüdigeret al. 2000, also for a review).

scholarly journals Lidar Observation of the Stratospheric Aerosol Layer over Okinawa, Japan, after the Mt. Pinatubo Volcanic Eruption

1993 ◽  
Vol 71 (6) ◽  
pp. 749-755 ◽  
Author(s):  
Tomohiro Nagai ◽  
Osamu Uchino ◽  
Toshifumi Fujimoto ◽  
Yoshinobu Sai ◽  
Kazuo Tamashiro ◽  
...  
Keyword(s):  
Volcanic Eruption ◽  
Stratospheric Aerosol ◽  
Aerosol Layer ◽  
Lidar Observation

Derivation of Mount Pinatubo stratospheric aerosol mean size distribution by means of a multiwavelength lidar

1994 ◽  
Vol 33 (24) ◽  
pp. 5690 ◽  
Author(s):  
Massimo Del Guasta ◽  
Marco Morandi ◽  
L. Stefanutti ◽  
B. Stein ◽  
J. P. Wolf
Keyword(s):  
Size Distribution ◽  
Stratospheric Aerosol ◽  
Mount Pinatubo ◽  
Mean Size ◽  
Multiwavelength Lidar

scholarly journals Intra-interglacial climate variability: model simulations of Marine Isotope Stages 1, 5, 11, 13, and 15

2016 ◽  
Vol 12 (3) ◽  
pp. 677-695 ◽  
Author(s):  
Rima Rachmayani ◽  
Matthias Prange ◽  
Michael Schulz
Keyword(s):  
Climate Variability ◽  
Surface Temperature ◽  
Northern Hemisphere ◽  
High Latitude ◽  
West African ◽  
Boreal Summer ◽  
The West ◽  
Temperature Anomalies ◽  
Astronomical Forcing

Abstract. Using the Community Climate System Model version 3 (CCSM3) including a dynamic global vegetation model, a set of 13 time slice experiments was carried out to study global climate variability between and within the Quaternary interglacials of Marine Isotope Stages (MISs) 1, 5, 11, 13, and 15. The selection of interglacial time slices was based on different aspects of inter- and intra-interglacial variability and associated astronomical forcing. The different effects of obliquity, precession, and greenhouse gas (GHG) forcing on global surface temperature and precipitation fields are illuminated. In most regions seasonal surface temperature anomalies can largely be explained by local insolation anomalies induced by the astronomical forcing. Climate feedbacks, however, may modify the surface temperature response in specific regions, most pronounced in the monsoon domains and the polar oceans. GHG forcing may also play an important role for seasonal temperature anomalies, especially at high latitudes and early Brunhes interglacials (MIS 13 and 15) when GHG concentrations were much lower than during the later interglacials. High- versus low-obliquity climates are generally characterized by strong warming over the Northern Hemisphere extratropics and slight cooling in the tropics during boreal summer. During boreal winter, a moderate cooling over large portions of the Northern Hemisphere continents and a strong warming at high southern latitudes is found. Beside the well-known role of precession, a significant role of obliquity in forcing the West African monsoon is identified. Other regional monsoon systems are less sensitive or not sensitive at all to obliquity variations during interglacials. Moreover, based on two specific time slices (394 and 615 ka), it is explicitly shown that the West African and Indian monsoon systems do not always vary in concert, challenging the concept of a global monsoon system on astronomical timescales. High obliquity can also explain relatively warm Northern Hemisphere high-latitude summer temperatures despite maximum precession around 495 ka (MIS 13). It is hypothesized that this obliquity-induced high-latitude warming may have prevented a glacial inception at that time.

scholarly journals The Sister Village Program: Promoting Community Resilience after Merapi Eruption

2018 ◽  
Vol 3 (1) ◽  
pp. 32
Author(s):  
Vita Elysia ◽  
Ake Wihadanto
Keyword(s):  
Local Government ◽  
Volcanic Eruption ◽  
Disaster Recovery ◽  
Local Level ◽  
Community Resilience ◽  
The World ◽  
Evacuation Routes ◽  
Post Disaster ◽  
Shed Light

Local Government of Magelang Regency initiates the Sister Village Program after Mount Merapi Eruption in 2010. The idea of this program is to connect villages at risk from Merapi eruption to partner villages with less risk in the surrounding regions. This program is part of post-disaster recovery initiatives at the local level which includes planned evacuation routes, shelters, provision of food and other daily essentials. This paper aims to shed light on the role of sister village program in promoting community resilience after the volcanic eruption of Merapi. It is found that the system of sister village program can fulfill many aspects of community resilience components. Considering Indonesia is one of the most disaster-prone countries in the world, this program should be regarded as a good example to be replicated in other prone areas in the country.

scholarly journals On the role of Eurasian autumn snow cover in dynamical seasonal predictions 

2021 ◽  
Author(s):  
Paolo Ruggieri ◽  
Marianna Benassi ◽  
Stefano Materia ◽  
Daniele Peano ◽  
Constantin Ardilouze ◽  
...  
Keyword(s):  
Snow Cover ◽  
Northern Hemisphere ◽  
Land Surface ◽  
General Circulation ◽  
Dominant Role ◽  
General Circulation Models ◽  
The Arctic ◽  
Seasonal Forecasts ◽  
Eurasian Snow

<p>Seasonal climate predictions leverage on many predictable or persistent components of the Earth system that can modify the state of the atmosphere and of relant weather related variable such as temprature and precipitation. With a dominant role of the ocean, the land surface provides predictability through various mechanisms, including snow cover, with particular reference to Autumn snow cover over the Eurasian continent. The snow cover alters the energy exchange between land surface and atmosphere and induces a diabatic cooling that in turn can affect the atmosphere both locally and remotely. Lagged relationships between snow cover in Eurasia and atmospheric modes of variability in the Northern Hemisphere have been investigated and documented but are deemed to be non-stationary and climate models typically do not reproduce observed relationships with consensus. The role of Autumn Eurasian snow in recent dynamical seasonal forecasts is therefore unclear. In this study we assess the role of Eurasian snow cover in a set of 5 operational seasonal forecast system characterized by a large ensemble size and a high atmospheric and oceanic resolution. Results are compemented with a set of targeted idealised simulations with atmospheric general circulation models forced by different snow cover conditions. Forecast systems reproduce realistically regional changes of the surface energy balance associated with snow cover variability. Retrospective forecasts and idealised sensitivity experiments converge in identifying a coherent change of the circulation in the Northern Hemisphere. This is compatible with a lagged but fast feedback from the snow to the Arctic Oscillation trough a tropospheric pathway.</p>

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