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Nuevas Perspectivas en la Ciencia Climática
Lo Que la EPA No Nos Está Diciendo


Introducción

Mañana, 29 de julio , 2003, el Comité de Obras Públicas y Ambiente del Senado de los EEUU, presidido por el Senador James Inhofe (R-OK), mantendrá una audiencia que hará historia examinando los recientes desarrollos en la ciencia del cambio de clima.

Mientras que el Comité del Senado se concentrará en los nuevos hallazgos sobre la historia del cambio climático, han existido notables avances en el área del cambio atmosférico global desde la publicación del ampliamente difundido Tercer Informe de Evaluación (TAR) del Panel Intergubernamental del Cambio Climático de los Naciones Unidas (IPCC), en el 2001. Este documento provee una revisión y vista general de nuevos e importantes trabajos publicados en la literatura científica arbitrada. Además, suministra una visión hacia el interior de la ciencia del clima manejada políticamente en las Naciones y en la Agencia de Protección del Ambiente de los EEUU.

La discusión científica está centrada en tres áreas:

• Nuevos trabajos sobre la historia de las temperaturas de superficie y sus implicaciones para un futuro calentamiento,

• Reconciliación de las temperaturas medidas por globos sondas y satélites que aumentan la confianza en un modesto aumento de la temperatura, al mismo tiempo que socava la credibilidad de los modelos climáticos computados que predicen un calentamiento dramático y,

• Descubrimientos recientemente publicados sobre mortalidad y cambio climático que argumentan muy seriemente contra los lúgubres escenarios de un aumento de las muertes urbanas ante las predicciones de calentamiento.

Juntos, estos estudios se integran, de manera creciente, a la noción de que el cambio climático será modesto y fácilmente adaptable por las economías libres y vibrantes.

Previas investigaciones han demostrado que el Protocolo de Kyoto y la Convención del Marco de Trabajo sobre Cambio Climático de las Naciones Unidas, no tendría un efecto mensurable sobre las tasas de calentamiento planetario. Este hallazgo, junto a las tres áreas mencionadas antes, trae una pregunta obvia: ¿Por qué debería haber alguna remanente credibilidad científica para el Protocolo? Como corolario, ¿por qué la Agencia de Protección del Ambiente, en esta o cualquier otra administración, continúa promoviendo la política del cambio climático? Mientras que la EPA puede haber "ignorado" al cambio climático en su Informe del Estado del Ambiente, la agencia tiene una clara historia reciente de exactamente lo opuesto, como se detalla en una sección posterior de este artículo.

Recientes Desarrollos en la Ciencia del Cambio Climático

Investigaciones Recientes Contradicen a las Afirmaciones de la EPA
y el IPCC Sobre un Calentamiento Anómalo de las Décadas Recientes

Durante casi cincuenta años, y a lo largo de literalmente miles de investigaciones presentadas en la literatura científica arbitrada, los científicos han establecido que el clima, desde el final de la última etapa glacial de hace unos 12.000 años, no ha sido para nada estable o constante. Entre cuatro y siete mil años atrás, la temperatura media superficial de la Tierra era de 1ºC a 2ºC más alta que hoy, por razones aún ignoradas. Es de notar que durante los años 80s, anteriores a la actual neurosis sobre el cacalentamiento global, los textos sobre el clima se referían a dicho período como "óptimo climático", porque el calentamiento trajo aparejado el florecimiento de la agricultura y la civilización.

En una escala de tiempo algo más corta, cientos de estudios de investigación documentaron dos excursiones climáticas relativamente recientes, concretamente la "Pequeña Edad de Hielo" (PEH), un período de tiempo frío que terminó aproximadamente hacia fines del Siglo 19, cuando las temperaturas globales o hemisféricas eran de aproximadamente 1ºC menores que el promedio para el Siglo 20, y un
"Período Cálido Medieval" (PCM), anterior al PEH, que fue 0,5ºC más cálido que el siglo pasado.

En 1999, Michael Mann, ahora profesor adjunto en la Universidad de Virginia y varios colegas, intentaron lo que se podría caracterizar muy bien como un meta-análisis de una más bien pequeña muestra de indicadores paleoclimáticos, que dieron nacimiento a lo que se conoce en la historia de la temperatura como el "Palo de Hockey", mostrado en la figura 1.



Figura 1: Reconstrucción de Mann et al. de las temperaturas del Hemisferio Norte para los pasados 1.000 años (también conocido como "El Palo de Hockey"), basados en mediciones "proxy". La región gris representa el rango de incerteza en las temperaturas reconstruídas (líneas azul).

Dada la inmensa cantidad de estudios sobre el cambio de clima en los últimos 1000 años, la atención que el IPCC le dio al "Palo de Hockey" fue desproporcionada. Fue publicado de manera prominente en el importante "Resumen para Hacedores de Políticas", del Tercer Informe de Evaluación (TAR) del 2001 del IPCC, sin ningún texto indicando que aunque interesante, al no encontrar ninguna Pequeña Edad de Hielo ni un Período Cálido Medieval, el estudio de Mann es un claro mentiroso en medio de un mar de estudios que indican lo contrario. Ha sido usado para la repetida cita de la reciente década "ha sido la más caliente en 1000 años".

De hecho, una cuidadosa inspección de la figura 1 revela que los esperadore márgenes de error dados por Mann et al., (1999) son verdaderamente enormes, y podrían muy bien incluir a la PEH y al PCM, en particular al primero (el PCM está en el rango extremo del error, pero existen muy pocos puntos de información que contribuyan a cualquier estimación global hace 1000 años). En realidad, es el promedio de los indicadores lo que atrajo una exagerada atención. Científicamente hablando, un promedio es una cifra sin utilidad alguna -a menos que los errores sobre ese promedio, resultado de muestreos estadísticos, errores de medición, y manipulación de datos, se de proporciones de manera explícita que, de hecho, fue lo que ocurrió en el caso del estudio de Mann de 1999.




Figura 2a: La respuesta de Soon y Baliunas (2003) a la pregunta "Hay una objetivamente discernible anomalía climática durante el período de la Pequeña Edad de Hielo 1300-1900) en este registro proxy?" Los cuadrados o recuadros rojos indican regiones donde la respuesta es "Si"; los círculos o recuadros verdes indican regiones donde la respuesta es "No". Los registros proxy de todo el mundo contienen abrumadoramente la firma del Pequeña Edad de Hielo.




Figura 2b
: La respuesta de Soon y Baliunas (2003) a su pregunta ""Hay una objetivamente discernible anomalía climática durante el Período Cálido Medieval (800-1300) en este registro proxy?" Los cuadrados y recuadros rojos indican regiones donde la respuesta es "Sì"; los círculos verdes indican las regiones donde la respuesta es "No"; y los triángulos o recuadros azules indican las regiones donde los resultados son inciertos. Los registros proxy de todo el mundo contienen, de manera abrumadora, la firma del Período Cálido Medieval.


El estudio de Mann era notable en el sentido que representaba un "collage" de otros estudios paleoclimáticos, aunque el tamaño de la muestra fue severamente limitado, con sólo 12 indicadores proxy formando los términos del promedio y error para el muy largo período desde el 1000 hasta el 1400.

Recientemente, Willie Soon y Sallie Baliunas, de la Universidad de Harvard, publicaron un completísimo estudio examinando una muestra mucho más amplia de las historias climátocas que las que fueron cubiertas en las primeras porciones del estudio de reconstrucción de series de temperaturas de Mann et al. Su investigación preguntaba si había algún indicador de la PEH o del PCM en estos registros. SE fijaron si había algún período cálido o frío de 50 años en las "ventas" de la PEH o del PCM que se desviara significativamente de las condiciones promedio del respectivo período. Bajo este criterio, Soon y Baliunas encontraron fuertes evidencias de la existencia de ambos períodos, la PEH y el PCM. Los resultados del estudio se muestran en las figuras 2a y 2b.

Existen más de 100 paleo-registros en el estudio de Sonn y Baliunas, muchos más que el número promedio usado por el estudio de Mann et all.

A pesar de las diferencias aparentes, los estudios de Mann et al., (1999) y el de Soon y Baliunas (2003), pueden ser reconciliados. Dado que el márgen de error en el estudio de Mann et al. es tan grande, puede acomodar tanto a la PEH como al PCM, como lo definen Soon y Baliunas. El debate Mann/Soon continuará durante un tiempo más. Recientemente (Julio 8, 2003), Mann y otros varios autores publicaron una defensa de su trabajo en la revista Transactions de la American Geophysical Union, pero el artículo de réplica, aún en preparación, tiene todavía que ser publicado.

La elección de las Naciones Unidas de sobreenfatizar el estudio de Mann et al., y de ignorar un tremendo volumen de otros trabajos ha tenido serias consecuencias, ya que fue la primera sanción "gubernamental" para el uso de una historia climática por encima de muchas otras. El "Palo de Hockey" fue publicado de manera prominente en el influyente informe del 2000 Impactos del Cambio Climático en los EEUU (Equipo Nacional de Síntesis de Evaluación 2000), conocido comúnmente como la "Evaluación Nacional" del cambio climático que publicó al "palo de Hockey" sin el acompañado "rango de error", un egregio ejemplo de mala conducta científica. Esto fue luego traducido al "Informe de Acción del Clima 2000" de la Agencia de Protección del Ambiente (EPA), cuyo Capítulo 6, "Impactos y Adaptaciones", se basó en la "Evaluación Nacional".

El uso que hizo la EPA de la "Evaluación Nacional" fue hecho con pleno conocimiento de que el documento contenía egregios errores científicos, incluyendo el uso de modelos del clima cuya performance era conocida por el "Equipo de Síntesis de Evaluación Nacional" como funcionando peor que una tabla de números aleatorios cuando se aplicaba a las temperaturas medias de 10 años de los Estados Unidos; vea la sección más abajo sobre el mal uso de la ciencia por parte de la EPA.




figure 3
: Globally averaged lower tropospheric temperature anomalies as measured by NASA satellites, December 1978 through June 2003.


Lower Atmospheric Temperature Trends, 1979–2002





figure 4
: A comparison of trends in satellite-measured temperatures (two columns on left) and weather balloon–measured temperatures (four columns on right, including one equal to zero).




figure 5
: Global averaged annual satellite, weather balloon (5,000–30,000 ft.), and surface temperature anomalies since 1979, the beginning of the satellite record.

While the controversy about UN and EPA overemphasis on the Mann history and the subsequent work of Soon and Baliunas is currently prominent, a number of other recent developments in climate change science are also worth noting.

The Importance of Satellite-Sensed Temperatures and Climate Change

Since their first publication in 1990 (Spencer and Christy 1990), tropospheric temperatures sensed by satellites have shown considerably less warming than surface histories, which is opposite to what is predicted by climate models that also project dramatic warming in the coming century.

The satellite record, which begins in late 1978, is approaching a quarter-century in length, as shown in figure 3, adjusted by John Christy for orbital decay and other drifts. In his most recent summarization of the satellite data, published in the Journal of Atmospheric and Oceanic Technology (Christy et al. 2003) shows a net global temperature trend of +0.06°c/decade, which is several times less than what was forecast by computer models that served as the basis for the original 1992 Framework Convention on Climate Change.

The trend, based upon monthly readings, is statistically significant. However, the trend, if based upon annual readings, is not. Note that at the current trend and variance levels, the annual data have a 50/50 chance of showing a significant warming by the end of 2007. However, the rate, noted above, is very low and it is doubtful that such a modest warming rate could have possibly provoked such an onerous treaty as the UN's Framework Convention on Climate Change; instead, that Convention was based upon lurid model results that are now known to be dramatic overestimations of human influence on the atmosphere.

In their recent paper, Christy and colleagues (2003) checked the accuracy of the satellite by comparing their record with a totally independent measurement of lower-atmosphere temperature, taken from daily weather balloons, and found the two to be in strong agreement. Weather balloons are launched twice daily from sites around the world; as they ascend through the atmosphere, they radio back observations of temperature, humidity, and pressure that are used to initialize models of daily weather forecasts. Balloon observations can be compiled into a record of lower-atmospheric temperatures that can then be compared with the satellite measurements.

It is important to realize that the way the weather-balloon data are collected is completely different from how we obtain satellite observations, and thus represent an independent measurement of the same quantity (atmospheric temperature). Of course, as is the case with any measurement, there are complications that must be considered when compiling the raw data.

For that reason, there are several different research groups that have released their own versions of the weather-balloon temperature history. To protect against any accusation of picking only the particular data set that best matches their satellite observations, Christy et al. (2003) compared the temperature trend during the past 24 years derived from their observations with the trend during the same period as calculated from four different manifestations of the global weather-balloon history.

Figure 4 shows the results. The trend in their satellite record, as noted above, is 0.06°c per decade. The trends from the various weather-balloon records range from -0.02°c per decade to 0.05°c per decade. In each case, the trend in the satellite record was slightly greater than that in the weather-balloon records, and the match with the two weather-balloon records with the most complete coverage of the globe was within 0.02°c. That close correspondence is remarkable and one of the great achievements in atmospheric science, as these are totally independent observations.

Figure 4 also shows another interpretation of the satellite data, by researchers Wentz and Schabel, that has yet to be published in the scientific literature. However, it is clear from the comparison with the independent weather balloon data that the Christy and Spencer trend is by far more reliable.

Figure 5 shows the entire concurrency for our three records of "global" temperature, which begins with the first complete year of the satellite MSU data, 1979. The record is now complete through its 24th year.

Figure 5 shows satellite temperatures, weather balloon temperatures roughly between 5,000 and 30,000 feet, and surface temperatures measured by thermometers. There is an increase in the surface record of 0.18°c/decade. Research by NASA scientists demonstrate that about 0.02°c/decade of this is a result of changes in the sun (Lean and Rind 1998), leaving a remaining 0.16°c/decade ascribable to human influence or other natural variation. The other two records show no statistically significant change.

The disparity between the surface, satellite and weather balloon readings is real (National Academy of Sciences 2000). The concordance between the satellites and balloons cannot be from chance, so there must be some process occurring in the lowest layers (below 5,000 feet) that is not being picked up in those two records.

Other Recent Climate Findings

Around the time of the publication of the IPCC TAR, a number of other findings were emerging in the refereed scientific literature that argued strongly against the alarmist view of climate change. These included:

• Discovery that observed surface warming is most consistent with a forecast at the low end of the 1.4–5.8°c range for global warming now projected by the United Nations (Michaels et al. 2002).

• Finding that the postwar ratio of winter-to-summer warming is greater than two-to-one (Balling et al. 1998).

• Over three-quarters of the cold half-year warming in the Northern Hemisphere since 1945 is confined to the very coldest airmasses. The warming outside of these airmasses is a minuscule 0.2°c per century (Michaels et al. 2000).

• The variation, or unpredictability, of regional temperatures has declined significantly on a global basis while there is no change for precipitation (Michaels et al. 1998).

• Maximum winds in hurricanes that affect the United States have significantly declined (IPCC 1996), and there is no evidence for a global increase in damaging storms (Landsea et al. 1996).

• The Kyoto Protocol to the United Nations Framework Convention on Climate Change will have no discernable impact on global climate within any reasonable policy timeframe (Wigley 1998).

Together, these findings—serious questioning of Mann's "hockey stick," validation of the satellite data, and the plethora of other reports documenting benign warming—should be sufficient to remove climate change as a viable political issue.

But this has not been the case, largely because of two additional factors. These include the spectre of dramatically increased urban mortality caused by global warming and the institutional culture of federal agencies, especially the Environmental Protection Agency, as demonstrated by the infamous National Assessment of global warming.

Global Warming and Urban Mortality

According to the National Assessment, "populations in urban areas are most vulnerable to adverse heat-related health outcomes. Heat indices and heat-related mortality rates are higher in the urban core than in surrounding areas." In the Second Assessment Report of the IPCC, we read that, based upon data from several North American cities, "the annual number of heatrelated deaths would approximately double by 2020 and would increase several-fold by 2050."

Together these statements provide national and international authority on the relationship between heat and mortality, with the obvious implication that warming of our cities will lead to increasing heat-related death.

In reality, without assistance from global warming, an experiment has been run in our cities for decades, as they warmed up from the well known "urban effect" on temperature. Bricks and buildings retain the heat of the day and impede ventilating winds. Most major urban core regions in the United States have warmed 1–2°c (Washington, DC being a prime example) as a result of simple urbanization. Consequently, large North American cities allow us to test whether increased temperature creates increased mortality.

On the surface, the arguments of the National Assessment and the IPCC seem absurd, implying no compensatory adaptation fueled by changing technology. To test hypotheses about warming and urban mortality, Davis et al. (2003) examined changes in the relationships between human mortality and hot, humid weather for 28 US cities with populations greater than one million on a decadal time scale. Twenty-nine years of daily total mortality rates (1964–1998 with some years missing in the early 1970s), standardized to account for changes in death rates related to inherent variations in the age of the population, were organized by decade for each city. Daily mortality rates were related to afternoon apparent temperatures— an index that combines temperature and humidity that serves as the basis of the summer Heat Index used by the National Weather Service. Davis et al. calculated the annual excess mortality on days when apparent temperatures exceeded a threshold value for 28 major metropolitan areas in the United States.

Figure 6a
shows daily mortality and apparent temperature for New York City. While mortality actually declines with heating, there are a number of clear excursions in death rates at the highest temperatures. These were simply extrapolated by the National Assessment and the IPCC to form future mortality expectations.

Yet, at the same time, it is very clear that infrastructure is very important. Figure 6b shows the same for Houston, a more modern city built near the very warm Gulf of Mexico. There is no excursion in the death rate on the hottest days.



figure 6a: Population-adjusted daily mortality vs. 4 pm apparent temperature for New York City.



figure 6b: Same as in (a) except for Houston. Notice that on the very hottest of days, the daily mortality in New York City rises rapidly, while the mortality in Houston shows no change.

Obviously, there is some personal and economic incentive to survive, so Davis et al. (2003) hypothesized that adaptation should lead to a general decline in urban heat-related mortality, and this is what the data show.

Contrary to the implied hypothesis in the National Assessment and the explicit assertion by the United Nations' IPCC, Davis et al. (2003) found that heat-related mortality rates declined over time in 22 of the 28 cities. For the 28-city average, there were 53 excess heat-related deaths per year (per standard million population) in the 1960s–70s, 25 in the 1980s, and 15 in the 1990s. In the 1960s–1970s, almost all study cities exhibited significantly above normal death rates on hot and humid days. During the 1980s, many cities, particularly those in the southern United States, exhibited no excess mortality. In the 1990s, this effect spread northward across interior cities.

The overall decadal decline in mortality in most cities is probably because of adaptations: increased air conditioning usage, improved health care, and heightened public awareness of the biophysical impacts of heat exposure. This finding of a more muted mortality response of the US populace to high apparent temperatures over time raises doubts about the validity of projections of future US mortality increases linked to potential greenhouse warming.

What could prompt such authoritative bodies such as the National Assessment "Synthesis Team" and the IPCC hypothesize and assert facts on warming and urban-related death that turn out to be so obviously false? Perhaps the answer lies in the culture of science.

Institutional Bias on Global Warming

The prominence of the Mann et al. record in the recent IPCC report, in the face of hundreds of other studies in the scientific literature is prima facie evidence of some type of political bias, as the obvious (and predictable) effect of emphasizing that history was to create a demand for climate intervention policy.

Public Choice theory offers a theoretical concept explaining patterns of behavior in such cases. Scientists maintain the crucial characteristics of any interest group. Environmental Science is an exclusive, small community, and over 99.5 percent of its research funding comes from the federal budget. Climate scientists know that there are many other scientific communities (cancer, heart disease, etc.) competing for that money. Climate scientists define themselves as providing "good" in the political sphere, which is the technical information required to save ourselves from impending climatic doom.

In the ethic of the environmental science community, the price of this "good" is now $4.2 billion per year (the proposed current federal budget for research on global environmental change). Competition requires that this community prove that "their" problem is much bigger, more urgent and needs more financial support than problems other interest groups want to solve by providing their own "good." This competition is not just limited to other science and technology enterprises, but includes all federal discretionary spending, such as housing for the homeless, a new federal facility in West Virginia, or fixing the space shuttle. Portraying climate change as a benign issue is a clear threat to the well-being of its scientific community, and there is logically a great resistance to this view.

Public Choice theory does not judge someone's honesty or dishonesty. It simply implies that the structure of incentives scientists face must create a bias of distortion, in which problems must be exaggerated in order to garner funding. Public Choice is a political process—based upon rhetoric as much as fact—and it provides mutual virtue for the scientists and the responsive politicians, an advantage to both, and a powerful adversary force against oderation on climate science or policy.

Consequently, there is an institutional bias towards drama and climate threat. Perhaps the most glaring recent example of EPA bias on global warming concerned its publication of the 2001 Climate Action Report (2001CAR), a public document detailing global warming science, projections, and possible policies.

The critical chapter of 2001CAR, Chapter 6 ("Impacts and Adaptation") relies heavily on the 2000 National Assessment of global warming, a Clinton Administration product that was based upon true miscarriages of science: It is predicated upon two models for future projections of climate that perform worse than a table of random numbers when applied to ten-year moving averages of US temperatures since 1900, and it removed the error bars from Mann's "hockey stick".

Here is an excerpt of a formal review of the 2001CAR by University of Virginia Professor of Environmental Sciences Patrick J. Michaels, and sent to the senior authorship of 2001CAR: The essential problem with the USCAR [2001CAR] is that it is based upon the USNA [The National Assessment]. That report is based largely on two climate models, neither one of which, when compared with the 10-year smoothed behavior of the lower 48 states (a very lenient comparison), reduces the residual variance below the raw variance of the data. The one that generates the most lurid warming scenarios—the Canadian Climate Centre (CCC) Model—produces much larger errors than are inherent in the natural noise of the data. That is a simple test of whether or not a model is valid …and both of the models used in the USNA fail. All implied effects, including the large temperature rise, are therefore based upon a multiple scientific failure. The USNA's use of those models and that approach is a willful choice to disregard the most fundamental of scientific rules. (And that they did not find and eliminate such an egregious error is testimony to grave bias). For that reason alone, the USCAR should be withdrawn from the public sphere until it becomes scientifically based.

EPA's 2001CAR, based upon the National Assessment, employed two climate models that were themselves outliers. One of them, the Canadian Climate Center (CCC) model, predicted the most extreme temperature changes, while the other, the UK model predicted the most extreme precipitation changes of all the models considered for inclusion. The CCC model forecasts the average temperature in the United States to rise 8.1°f (4.5°c) by the year 2100, more than twice the rise of 3.6°f (2.0°c) forecast by the UK model (the second model used in the USNA). Compare this with what has actually occurred during the past century. The CCC model predicted a warming of 2.7°f (1.5°c) in the United States over the course of the twentieth century, but the observations published by the U.S. National Climatic Data Center show that the increase was about 0.5°f (0.3°c), or about 5 times less than the forecast.

If the observed ratio continues into the future, the US temperature increase by the year 2100 will be around 1°f and hardly noticeable. The UK forecast of precipitation changes across the Unites States is nearly as extreme. Of all the models reviewed for inclusion in the USNA (and, consequently, for 2001CAR), the UK model predicted more than twice the precipitation change than the second most extreme model, which was the CCC model. The CCC model
itself forecast twice the change of the average of the remaining, unselected models. Therefore, along with the fact that climate models in general cannot accurately forecast climate change at regional levels, the climate models selected as the basis for the USNA conclusions do not even fairly represent the collection of available climate models.

What is remarkable is that EPA went forward with 2001CAR in full knowledge of these problems.

Conclusion

As the Senate Environment and Public Works Committee prepares for an important hearing on new developments in the ongoing debate about past climate change, it is important to recognize that there have been a number of additional advances in climate science, many of which were concurrent or after the publication of the most recent (2001) Assessment of Climate Change By the United Nations Intergovernmental Panel on Climate Change, and the 2000 National Assessment of U.S. Climate Change. This latter document was used extensively by the U.S. Environmental Protection agency in its 2001 Climate Action Report.

As shown in this paper, critical portions of science in all of these reports are misleading, inaccurate, unreliable, or simply wrong. However, that is not an indictment of the individuals involved, but is rather more symptomatic of the nature of science when funded by a government leviathan.

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