Category Archives: Climate Science Presentations

The Importance of Land Use/Land Practices On Climate – A Perspective From Jon Foley

In 2007, I posted

Presentation On Global Change and Climate Change By Jon Foley At The April 4-6, 2007 NASA Land-Cover and Land-Use Change Meeting

From his website

Jonathan Foley is the director of the Institute on the Environment (IonE) at the University of Minnesota, where he is a professor and McKnight Presidential Chair in the Department of Ecology, Evolution and Behavior. He also leads the IonE’s Global Landscapes Initiative.

The title of Jon’s talk was

Planet Against the Grain

As a result of a committee I am on [which I will have more to say about at a later date], there remains the misunderstanding with respect to the role of human land management on the climate system. Jon Foley’s powerpoint presentation is among the very best at documenting the role of human land management as a first order climate system (and environmental) forcing.

Examples of his view (which I agree with) are summarized in his talk. These include

  • massive changes to Earth’s land ~40% of land converted to agriculture [from slide 7]
  • massive increases in water use – water use tripled in 50 years – mostly due to agriculture – 70% irrigation, 20% industry, 10% domestic [from slide 8]
  • massive release of excess nutrients doubling natural nitrogen, phosphorus flows polluted lakes and rivers coastal “dead zones” [from slide 9]

Jon introduces a key finding that

land use practices are changing quickly; much more than changing land cover [from slide 30]

With respect to greenhouse emissions, he states that

wow! global land use & agriculture, taken together, contribute more greenhouse gases than any single societal activity; altogether, agriculture and deforestation appear to contribute at least 1/3 of all GHG forcing

In regards to using a global average metric to characterize changes in the climate system, he wrote that land use

often get “washed out” in outdated climate metrics of radiative forcing and global mean temperature [from slide 44]

He writes the overarching theme of his talk includes that

Bottom Line Global Change is Much More Than CO2 and Global Warming [from slide 46]

and that

Current Focus on CO2 / Climate Connection is Very Short Sighted [from slide 54]

Jon’s perspective can be read in his papers, such as

Foley et al 2005: Global Consequences of Land Use. Science. Science 22 July 2005: 570-574. [DOI:10.1126/science.1111772]


Foley et al, 2011: Solutions for a cultivated planet. Nature478, 337-342 doi:10.1038/nature10452

In his 2011 article he wrote

Agriculture is now a dominant force behind many environmental threats, including climate change, biodiversity loss and degradation of land and freshwater…. In fact, agriculture is a major force driving the environment beyond the ‘‘planetary boundaries’’ ….

I also highly recommend Jon’s talk

“The Other Inconvenient Truth” – Jon Foley, TECxTC presentation. Watch the video on YouTube

Clearly,  climate assessments that focus primarily on CO2 and a few other greenhouse gases are inappropriately too narrow.

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Seminar “The Interannual Variability Of The Tropical Atmosphere” By Calvin Liang September 19 2012

There is an interesting upcoming seminar. I have presented the announcement below with highlight added.

Chemical Sciences Division Seminar

Calvin Liang


The Interannual Variability of the Tropical Atmosphere

Wednesday, September 19, 3:30 PM MDT (Refreshments at 3:15 PM)  David Skaggs Research Center, Room 2A305

The primary tropical interannual modes of variability are the El Nino Southern Oscillation and quasibiennial oscillation (QBO). We find through satellite remote sensing soundings of temperature and water vapor, from the A-Train constellation of satellites, that the ENSO and QBO jointly impact the tropical tropopause layer (TTL) temperature and water vapor distribution. Although the QBO is a zonally symmetric phenomenon, the ENSO breaks that symmetry via the migration of convection between the tropical western Pacific (TWP) and the tropical central Pacific (TCP). Furthermore, we find that the joint impacts depend on the relative phase of the ENSO and QBO with TWP  (TCP) experiencing enhanced (reduced) anomalies when these modes are in phase. When the ENSO and QBO fall out of phase the anomaly enhancement (reduction) migrates to the TCP (TWP). Our results indicate that processes in the TCP may have a pronounced impact on the zonal mean TTL water vapor distribution when the ENSO and QBO are out of phase.

Furthermore we quantify the ENSO and QBO interannual impacts on the tropical cloud distribution as seen by CloudSat and CALIPSO. The results show the distinct impact of ENSO induced SST anomalies on the migration of convection. However, we also find that ENSO impacts all the prominent tropical cloud types with their anomalies following water vapor from the boundary layer up to ~13-14 km, and temperature at higher altitudes. Another robust feature is the eastward tilt signature of Kelvin waves on the cloud distribution in the TWP, consistent with the eastward tilt of temperature anomalies in the same region in the TTL. This lends credence to the hypothesis that cloud amount is primarily determined by temperature variance in the TTL. A statistically significant QBO signal in cloud amount is also observed.

Seminar attendees agree not to cite, quote, record, copy, or distribute material  presented without the explicit written consent of the seminar presenter. Any opinions expressed in this seminar are those of the speaker alone and do not necessarily reflect the opinions of NOAA or ESRL/CSD.

To view this seminar remotely you can reserve your Webinar seat now at:

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Seminar Announcement “Impacts of Forests And Land Use On Chemistry-Climate Interactions” By Nadine Unger

There is an interesting seminar next this week. The topic provides another example of the complexity of the climate system as affected by human activity. I have reproduced the seminar announcement below. The url version of it can be downloaded from this website address.

Chemical Sciences Division Seminar ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Impacts of forests and land use on  chemistry-climate interactions by Professor Nadine Unger of Yale University

Wednesday, September 5, 3:30 PM (Refreshments at 3:15 PM)  David Skaggs Research  Center, Room 2A305

The abstract reads [highlight added]

The short-lived climate forcers (SLCFs) ozone, methane and aerosol particulates and their indirect effects on cloud properties significantly impact regional and  global climate but in complex ways involving both warming and cooling mechanisms. Selective reduction of the warming SLCFs is currently receiving attention as a way of mitigating near-term warming, reducing the rate of warming (important for adaptation of ecosystems) and simultaneously improving air quality. To date, the feedbacks from anthropogenic land cover change have not been considered in assessments of historical and future SLCFs. Lack of quantitative information of these changing interactions, which perturb emissions of reactive carbon from vegetation, deposition rates of pollution to ecosystems and the underlying surface albedo, represents a  major uncertainty in the ability to assess the climate and air quality benefits  of reductions in the SLCFs. Here, a global chemistry-climate model (NASA ModelE-Y) with a new interactive vegetation biophysics module that incorporates photosynthesis-dependent isoprenoid emissions is applied to quantify the effects of historical (1850 – 2005) cropland expansion on the SLCFs. The resultant biogenic organic aerosol direct radiative forcing entirely counteracts the biophysical (albedo) forcing (+0.16 versus -0.09 W/m2). The land cover change alone implies a 15% longer methane lifetime in 1850  than 2005 while overall net effects on ozone radiative forcing are small. The analyses are extended to integrate the effects of future anthropogenic land cover change into projected aggressive air pollution emission abatement scenarios.

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Kumiko Tsujimoto Seminar “Land-Lake-Atmosphere Interaction And Its Associated Local Rainfalls During The Post-Monsoon Season In Cambodia”

I have been alerted to a new colleague who is working on the land-atmosphere interaction issue with respect to land-use/land cover change. Her name is Kumiko Tsujimoto of the Department of Civil Engineering of the University of Tokyo and her biographical sketch is given below. She will be visiting the USA this Fall and as I learn of the  specific  times and locations of her seminar, I will post.

Kumiko Tsujimoto’s Biographical Sketch

My major is hydrology, including both surface hydrology and hydrometeorology. My major study area is Cambodia and I have been working for that country for the past 9 years. Since I have a background on agriculture, global environment studies, and civil engineering, I am interested in how to use the knowledge and technology of hydrology in order to contribute to the disaster mitigation, poverty reduction, and environmental conservation in the developing countries.

March 2009 Ph.D. Civil Engineering, The University of Tokyo
March 2006 M.S. Global Environmental Studies, Kyoto University
March 2004 B.S. Agriculture, Kyoto University

Peer-reviewed papers:
1) Takahashi J., T. Katsuyama, K. Tsujimoto, M.Yasunaka; Present State and Prospects of International Research Activities for Food and Water Issues, Journal of the Japanese Society of Irrigation, Drainage and Reclamation Engineering 73(3), 189-193, 2005, in Japanese with English abstract
2) Masumoto T., K. Tsujimoto, H.Somura; Hydro-meteorological Observation and Analysis of Observed Data at Tonle Sap Lake and its Environs, Urban and Paddy Areas, Technical Report of National Institute for Rural Engineering, 206, pp.219-236, 2007, in Japanese with English abstract
3) Tsujimoto K., T. Masumoto and T. Mitsuno, Seasonal changes in radiation and evaporation implied from the diurnal distribution of rainfall in the Lower Mekong, Hydrological Processes, Vol.22, pp.1257-1266, 2008.
4) Tsujimoto K. and T. Koike: Mechanism of locally-induced convection development and its effects on vapour transportation over the Tonle Sap Lake Area, Annual Journal of Hydraulic Engineering, 52, 247-252, 2008, in Japanese with English abstract
5) Tsujimoto K., and T. Koike: Effects of the locally-induced precipitation on the stream flow during the dry-season at the vicinities of the Tonle Sap Lake, Annual Journal of Hydraulic Engineering, 53, 337-342, 2009, in Japanese with English abstract
6) Tsujimoto K. and T. Koike: Interaction of large-scale atmospheric condition and local circulation which affects Cambodian post-monsoon rainfalls, Annual Journal of Hydraulic Engineering, 55, 463-468, 2011, in Japanese with English abstract
7) Tsujimoto K. and T. Koike:Two diurnal cycle systems with different spatial scales and their effects on the post-monsoon rainfall in the inland of the Indochina Peninsula, Journal of Japan Society of Civil Engineering B1 (Hydraulic Engineering) 68-4, I_451~I_456, 2012, in Japanese with English abstract
8) Tsujimoto K. and T. Koike, Requisite conditions for post-monsoon rainfall in Cambodia, Journal of Hydroscience & Hydraulic Engineering, 31-1, 1-14, 2012.

Her provisional abstract for the presentation is

Kumiko Tsujimoto
Research associate

Department of Civil Engineering, The University of Tokyo
Presentation Title:

Land-lake-atmosphere Interaction and its associated local rainfalls during the post-monsoon season in Cambodia

Presentation Abstract

Cambodia is located in the Lower Mekong River Basin, in the Indochina Peninsula. In the center of this country, there is a lake called Tonle Sap Lake. This lake is the largest freshwater lake in Southeast Asia and has a very unique hydrological characteristic that its lake area changes dramatically within a year: it is about 2,500km2 at the end of the dry season but it reaches to more than 10,000km2 at the end of the rainy season. This seasonal expansion occurs as a result of the seasonal change of the water level of the Mekong River. Therefore, if the basin development such as dam construction changes the flow regime of the Mekong River, it will in turn change the season al change of the lake area as well.

With this background, this study aims to make an environmental assessment on what will happen by the possible/on-going basin development in the upper Mekong River Basin. The impacts on the local atmospheric water circulation brought by the change of the lake area is focused on, since there have been no studies which target the land-lake-atmosphere interaction.

By integrating numerical models, satellite data, and ground data, the unique local atmospheric water circulation was found and its mechanism was revealed. The mechanism will be highlighted in the presentation.

Although this study is a geophysical research, it was also revealed that this phenomenon brings rainfalls at western Cambodia even after the end of the summer monsoon. Since western Cambodia is the most agriculturally productive area in this country, it would be possible that the locally-driven rainfall by the lake supports the current agricultural system in this region. Therefore, again, the possible/on-going basin development in the upper Mekong River Basin might affect the agricultural production in the granary of Cambodia and thus affect the food security in this country.

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Seminar Announcement “Black Carbon Aerosols Over An Urban Region: Characteristics, Mixing And Radiative Forcing” By S. Ramachandran

I received the seminar announcement this morning. Since the topic illustrates an example of the diversity of climate forcings beyond the greenhouse gases, I am posting it.

S. Ramachandran Physical Research Laboratory, Ahmedabad, India

Black carbon aerosols over an urban region: Characteristics, Mixing and Radiative Forcing

Tuesday, August 21, 10:00- 11:00 AM David Skaggs Research Center, Room 2A305

The abstract reads [highlight added]

Black carbon (BC), among the carbonaceous aerosols, is gaining considerable significance because of its ability to influence air quality and climate on local, regional and global scales. Black carbon aerosols are produced as primary particles from incomplete combustion processes such as fossil fuel and biomass burning, and hence most of the BC in the atmosphere originates from man-made activities. The radiative and climate impacts of BC are increasingly recognized as BC can absorb sunlight, heat the air and contribute to global warming, unlike the other aerosol types (e.g., sulfate) which produce cooling.Both absorbing (BC) and scattering (sulfate) aerosols cool the surface by reducing the incoming solar radiation and cause solar dimming. In the atmosphere aerosols exist in different mixing states. Mixing of aerosols can change the size distribution of aerosols, their life cycle and radiative effects. The diversity of aerosols present over a location due to local sources and long range transport can give rise to a complex aerosol mixture. Assumptions on the state of aerosol mixing and its effect on optical properties give rise to uncertainties in modeling of direct as well as indirect climate forcing of aerosols.

The seminar will focus on the monthly/seasonal mean variations in physical and optical characteristics of aerosols over an urban region, and the resultant radiative effects with an emphasis on the black carbon owing to its crucial role in regional and global climate impacts.  Results obtained on the probable mixing states of aerosols and  their radiative effects over the study location, the climate impact in terms of  the heating rates (K/day) for different scenarios of BC mass concentrations and  zero BC conditions will be presented and discussed.

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Perspective On The Hot and Dry Continental USA For 2012 Based On The Research Of Judy Curry and Of McCabe Et Al 2004

Photo is from June 26 2012 showing start of the June 26 Flagstaff fire near Boulder Colorado

I was alerted to an excellent presentation by Judy Curry [h/t to Don Bishop] which provides an informative explanation of the current hot and dry weather in the USA. The presentation is titled

Climate Dimensions of the Water Cycle by Judy Curry

First, there is an insightful statement by Judy where she writes in slide 5

CMIP century scale simulations are designed for assessing sensitivity to greenhouse gases using emissions scenarios They are not fit for the purpose of inferring decadal scale or regional climate variability, or assessing variations associated with natural forcing and internal variability. Downscaling does not help.

We need a much broader range of scenarios for regions (historical data, simple models, statistical models, paleoclimate analyses, etc). Permit creatively constructed scenarios as long as they can’t be falsified as incompatible with background knowledge.

With respect to the current hot and dry weather, the paper referenced by Judy in her Powerpoint talk

Gregory J. McCabe, Michael A. Palecki, and Julio L. Betancourt, 2004: Pacific and Atlantic Ocean influences on multidecadal drought frequency in the United States. PNAS 2004 101 (12) 4136-4141; published ahead of print March 11, 2004, doi:10.1073/pnas.0306738101

has the abstract [highlight added]

More than half (52%) of the spatial and temporal variance in multidecadal drought frequency over the conterminous United States is attributable to the Pacific Decadal Oscillation (PDO) and the Atlantic Multidecadal Oscillation (AMO). An additional 22% of the variance in drought frequency is related to a complex spatial pattern of positive and negative trends in drought occurrence possibly related to increasing Northern Hemisphere temperatures or some other unidirectional climate trend. Recent droughts with broad impacts over the conterminous U.S. (1996, 1999–2002) were associated with North Atlantic warming (positive AMO) and northeastern and tropical Pacific cooling (negative PDO). Much of the long-term predictability of drought frequency may reside in the multidecadal behavior of the North Atlantic Ocean. Should the current positive AMO (warm North Atlantic) conditions persist into the upcoming decade, we suggest two possible drought scenarios that resemble the continental-scale patterns of the 1930s (positive PDO) and 1950s (negative PDO) drought.

They also present the figure below with the title “Impact of AMO, PDO on 20-yr drought frequency (1900-1999)”.   The figures correspond to A: Warm PDO, cool AMO; B: Cool PDO, cool AMO; C: Warm PDO, warm AMO and D:  Cool PDO, warm AMO

The current Drought Monitor analysis shows a remarkable agreement with D, as shown below

As Judy shows in her talk (slide 8) since 1995 we have been in a warm phase of the AMO and have entered a cool phase of the PDO. This corresponds to D in the above figure.  Thus the current drought and heat is not an unprecedented event but part of the variations in atmospheric-ocean circulation features that we have seen in the past.  This reinforces what Judy wrote that

[w]e need a much broader range of scenarios for regions (historical data, simple models, statistical models, paleoclimate analyses

in our assessment of risks to key resources due to climate. Insightful discussions of the importance of these circulation features are also presented, as just a few excellent examples, by Joe Daleo  and Joe Bistardi on ICECAP, by Bob Tisdale at Bob Tisdale – Climate Observations, and in posts on Anthony Watts’s weblog Watts Up With That.

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“Global Warming Or Not? The Relative Roles Of Externally Forced Versus Internally Generated Decadal Climate ” By Gerald A. Meehl, NCAR

Seminar Announcement

I am pleased that the role of internal climate dynamics in climate system heat changes (and other aspects of the climate system) is finally becoming better appreciated. This movement towards a broader view is ot be presented in the seminar below [h/t to Jason English]. Note that the talk will be live webcast at This abstract is an important new contribution to our understanding of how the climate system works [highlight added]

Global warming or not? The relative roles of externally forced versus internally generated decadal climate “

Tuesday, 15 May, 2012
3:30 p.m. Mesa Lab, Main Seminar Room
NCAR, 1850 Table Mesa Drive

The last decade has been marked by very little globally averaged warming trend. This has led some to conclude that global warming has stopped for good. However, there have been previous decades when there was little or no global temperature increase set against the background of a longer term warming trend. This raises the issue of the relative roles of internally generated decadal climate variability and externally forced climate system response. The mid-1970s climate shift is given as an example of globally averaged temperatures dramatically rising after a period of little warming. Results show that this shift was part internally generated, related to a transition from a negative to positive phase of the Interdecadal Pacific Oscillation (IPO), and part externally forced by increasing greenhouse gases (GHGs) with a possible contribution from solar forcing. To better understand the recent period of little warming, 21st century simulations with CCSM4 are analyzed to show that during decades of slightly negative global temperature trend, the IPO is in a negative phase, along with reductions of Antarctic Bottom Water (AABW) formation and a weaker Atlantic Meridional Overturning Circulation (AMOC). Thus, during hiatus decades, the excess heat being trapped in the system due to increasing GHGs goes into the deep ocean. Conversely, decades in the model when there is an unusually large positive global temperature trend show the opposite response. This highlights the importance of understanding relative contributions of external forcing and internally generated variability for the decadal climate prediction problem.

My Comments:

  • First, if  “excess heat [is] being trapped in the system due to increasing GHGs…. into the deep ocean” this heat may be sequestered there indefinitely. It is not clear how such heat could be quickly transferred back into the atmosphere.
  • Moreover, what is the magnitude of the flux of heat through the upper 700m of the ocean in the model, and can this be seen in the real world observations?
  • Finally, this is yet another example of why the use of the global average surface temperature trend (which does not sample this heat when it is used to diagnose global warming) is a very inadequate metric for this purpose.

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Presentation Titled Promoting “The Value Of Water Cycle Remote Sensing Missions And Climate Studies To Non-Traditional Consumers” By Faisal Hossain

I want to alert you to an excellent powerpoint slide presentation by Faisal Hossain of Tennessee Technological University titled

Promoting the Value of Water Cycle Remote Sensing Missions and Climate Studies to Non-Traditional Consumers

The talk was presented on March 12 2012 at the Jet Propulsion Laboratory.

As written in the seminar announcement

Dr. Faisal Hossain is an Associate Professor in the Civil Engineering Department of Tennessee Technological University. He holds a B.S in Civil Engineering from the Indian Institute of Technology, an M.S. from the National University of Singapore and a Ph.D. from the University of Connecticut. His research interests lie in the field of water resources, remote sensing and education. He received a NASA New Investigator Program Award in 2008 and an American Society of Engineering Education Outstanding New Faculty Research Award in 2009. Currently, he is leading a capacity-building initiative to train staff in developing nations to better harness the potential of satellite remote-sensing missions.

The slides go through these three topics

Societal (Application) Value for Non-traditional Consumers.

Key findings of Recent Application-driven Research

Packaging the Research as a Product for Consumers: Lessons Learned and Way Forward

with a focus on

Water Cycle Remote Sensing: Tactical Scale of Decision Making (Transboundary Flood Management)

Climate Studies: Strategic Scale of Decision Making (Design and Operations of Large Dams)

With respect to water cycle remote sensing he writes that the consumer he is considering is the public community (transboundary flood management) who have time scales of decision making of days to weeks. For climate studies he is considering the engineering community in terms of the design and operation of large dams in which the time scale for decision making is years to decades.

His recommendations for a way forward on these issues are:

  • More Hands-on Education Effort involving (active learning) of consumers (stakeholders)
  • Co-design of Research Experiments with input from consumers.
  • Working with Philanthropic Institutions: Broaden the value of water cycle satellites (beyond water – health, food, poverty) to increase appeal to non traditional consumers. Is it possible to make massive amounts of satellite water data freely accessible on a daily basis to people around the world (much like Google Earth –intuitive design)?
  • Search Engine Optimization – Simple Issue involving social science (but can reach out to millions of web users)

I recommend viewing the entire talk as it fits with our bottom-up, resource-based focus that we discuss in our paper

Pielke Sr., R.A., R. Wilby, D. Niyogi, F. Hossain, K. Dairuku, J. Adegoke, G. Kallos, T. Seastedt, and K. Suding, 2012: Dealing  with complexity and extreme events using a bottom-up, resource-based  vulnerability perspective. AGU Monograph on Complexity and  Extreme Events in Geosciences, in press.

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Seminar Announcement “On The Origins, Dynamics, And Predictive Power Of Large-Scale, Low-Frequency Variations In North Atlantic Circulation” By Steve Yeager

There is an upcoming seminar at The University of Colorado which provides further information on what is currently achievable in terms of long term climate system forecasts; see also

Guest Post Titled “Decadal Prediction Skill In A Multi-Model Ensemble” By Geert Jan van Oldenborgh, Francisco J. Doblas-Reyes, Bert Wouters, Wilco Hazeleger

The seminar is the Comprehensive Eaxm of Steve Yaeger [highlight added]. We need more such studies.


DATE and TIME: Monday, March 19, 2012 at 9:00am LOCATION: ATOC Conference Room, Folsom Stadium 255-12 (see directions below)

TITLE:  “On the origins, dynamics, and predictive power of large-scale, low-frequency variations in North Atlantic circulation”


An ensemble of initialized decadal prediction (DP) experiments using the Community Climate System Model, version 4 (CCSM4) shows significant skill at forecasting changes in North Atlantic upper ocean heat content and surface temperature up to a decade in advance.  Coupled model ensembles integrated forward from 10 different start dates spanning 1961 to 2006 with ocean and sea-ice initial conditions obtained from a forced historical experiment (CORE-IA) are found to exhibit a good correspondence with late 20th century ocean observations from the North Atlantic subpolar gyre (SPG) region.   A budget of SPG heat content from the CORE-IA experiment demonstrates the extent to which low-frequency changes in ocean heat advection related to the Atlantic meridional overturning circulation (AMOC) dominated temperature tendencies in this region over the latter half of the 20th century.  Heat budgets computed from the DP ensembles reveal that large advective heat flux anomalies from the  south are highly correlated with those from CORE-IA, and thus the skill of the CCSM4 decadal prediction system in the SPG region is attributable to correct initialization of large-scale ocean circulation anomalies.  These results lend support to the hypothesis that improved AMOC prediction could greatly extend the lead time for skillful prediction of North Atlantic SST and associated climate variations.

However, advances in decadal prediction will require a deeper understanding of the mechanisms which drive low-frequency AMOC variations in general circulation models; the sensitivity of these mechanisms to the model mean state and to sub-gridscale processes which may or may not be parameterized; and the overall fidelity of model-simulated behavior to that found in nature.  Towards that end, a vorticity diagnostics tool has been developed to facilitate the analysis of CCSM4 ocean model output.  The tool is applied here to the CORE-IAsolution, as well as to two companion hindcasts which isolate the buoyancy- and wind-driven components of surface forcing, in order to elucidate the  ocean dynamical response to historical forcings. The mean vorticity balance of the CORE-IA control reveals the key role played by flow-bathymetry interactions in setting the strengths of the Atlantic MOC and subpolar gyre circulation and the location of the North Atlantic current, in the POP model.

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Another Example Of The Misuse Of Multi-Decadal Global Climate Model Predictions

I have posted numerous times on the lack of scientific robustness in using multi-decadal global climate model predictions for impact studies (e.g. see and see). On Wednesday I posted a guest contribution from Geert Jan van Oldenborgh (see) which reported finding only very limited decadal predictive skill for a few geographic areas.  Their research provides further confirmation of our conclusions in

Pielke Sr., R.A., and R.L. Wilby, 2012: Regional climate downscaling – what’s the point? Eos Forum,  93, No. 5, 52-53, doi:10.1029/2012EO050008

that [where type 4 downscaling refers to multi-decadal climate predictions]

“…..for regional downscaling (and global) models to add value (beyond what is available to the impacts community via the historical, recent paleorecord and a worst case sequence of days), they must be able to skillfully predict changes in regional weather statistics in response to human climate forcings. This is a greater challenge than even skillfully simulating current weather statistics…….It is therefore inappropriate to present type 4 results to the impacts community as reflecting more than a subset of possible future climate risks.”

There is a seminar tomorrow that exemplifies the continued misuse of these model results.  The announcement for the talk reads [highlight added]

Fri Mar 09,          03:30 pm.                    NOTE LOCATION:  IBS Building, room 155

Catching Climate Fever: Diagnosing the Changing Environment of Infectious Disease?

Andrew Comrie

University of Arizona, Associate Vice President for Research and Dean of the Graduate College and School of Geography and Development×70.png

Andrew Comrie

University of Arizona, Associate Vice President for Research and Dean of the Graduate College and School of Geography and Development

Abstract: What are the disease impacts of climate change? Climate-health research is a rapidly expanding field that intersects multiple disciplines and approaches. I review key concepts using a range of infectious disease examples from my own research group, and then focus on mosquito vectors of disease in the US. Climate and climate change affect the ecology of infectious diseases via disease hosts, vectors, and reservoirs. In the southern United States, Culex quinquefasciatus may be a primary vector for West Nile Virus (WNV) in many locations because of its affinity for urban environments and because they feed on humans and bird hosts. Changes in temperature and precipitation regimes may affect the population and season length of this mosquito, altering the risk of WNV transmission to humans. It is difficult to assess the impact of climate changes on local mosquito populations, given the paucity of observations, and therefore we have developed the Dynamic Mosquito Simulation Model (DyMSiM). Using downscaled general circulation model (GCM) projections for current and future conditions, we modeled mosquito population dynamics across the southern United States using DyMSiM. As expected, modeled mosquito populations responded differently by location, season, and time period. Temperature changes have a marked positive effect on mosquito population in fall, while summer showed a strong positive link between precipitation and mosquito populations. Higher temperatures led to a rise in populations during the cooler months, but during summer decreased breeding habitats due to drying from evaporation. In the Western US, projected drier conditions did not decrease mosquito populations because they rely heavily on permanent water sources which are not controlled by precipitation.

Refreshments following lecture on the IBS patio.

This lecture series was made possible by the generous support from The Beirne Carter Foundation.

Co-sponsored by the Environment and Society Program of the Institute of Behavioral Science and CIRES Center for Science and Technology Policy Research.

While the sensitivity of mosquito populations to weather and climate part of the talk may be quite interesting and robust, the claim to be able to predict changes in these populations in coming decades due to changes in the statistics of the climate system is yet another inappropriate use of climate modeling.

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