I cambiamenti climatici e le loro cause: una discussione ...

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I cambiamenti climatici e le loro cause: una discussione su alcuni punti chiave

Nicola ScafettaAllumiere02/27/2010

L'atmosfera terrestre e' composta di

Nitrogen0 (~78 percent)Ossigeno (~21 percent)

Vapore acqueo 0-4%

CO2 0.035%,

Metano 0.0002%

Ozono 0.000004%.

IPCC: se il CO2 raddoppia, la temperatura aumenta in media tra 1.5 e 4.5 oC

Knutti & Hegerl, 2008

La teoria dell'effetto serra e' basata su due teorie indipendenti

Enorme incertezza

L'effetto delle nuvole

Perche' le nuvole sono Importanti per i cambi climatici

Un link tra lo spazio exstraterrestre e il clima terrestre

Svensmark et al. (2009); Kirkby J. (2007)

Kirkby J. (2007)

Una forte attivita' solareprotegge la Terra dai raggi cosmici

Meno raggi cosmici implicano meno isotopi C14 , Be10 sulla Terra

Kerr, Science 2001

Cicli di 1000 anni

Correlazione tra l'attivita' solare e la storia umana

Eddy J.A. (1976), The Maunder Minimum, Science 192, 1189-1202.

IPCC 2001-2007: Il sole e 'il clima non son opiu' correlati sin dal 1975

Solanki's TSI proxy model

The good correlationends in 1975 !

Only sun and volcano

All forcings

La teoria del riscaldamento globale antropico dell'IPCC

100% del riscaldamento ossevato sin dal 1960e' antropico

Hansen et al. “Climate simulations for 1880–2003 with GISS ModelE,” Clim Dyn (2007) 29:661–696

GISS modelE (blue)fails to reproduce the climate variabilitybefore 1960

warming cooling warming cooling warming

cooling ?

Temperatura globale della superficie Predizione di un modello climatico

Possiamo credere all'IPCC?

Failure to reproduce the climate variabilitybefore 1960

Failure to reproduce the cooling after 2002

Cosa sta cambiando il clima ?

Global Surface Temperature (CRU)

1/1/1990 1/1/1999

BEFORE 1998

La temperatura dell' “Hockey Stick” (Mann, Bradley, Hughes 1998)

0.2

Scafetta, EPA 2009

Crowley,Science 289, 270-277 (2000)

Energy balance model simulation

Mann's temp

Scafetta, EPA 2009

Input forcings

Output temp. signatures

Sin dal 2004 si hanno a disposizione nuove ricostruzioni della temperatura. (Moberg et. al, Nature 2005; Huang et al, GRL 2004.)

Modello di Crowley

e

Temperatura di Moberg et al, (2005)

Crowley's 2000 energy balance modelfails to reconstruct Moberg's temperature.

This temperature record suggests that the model is seriously underestimating the solar effect on climateand overestimating thevolcano and GHG effects.

Would global warmingdebate be different ifMoberg published in 1998?

Scafetta, EPA 2009

a) filtered global surface temperature data with the decadal modulation associated to solar cycle; b) global surface temperature data; c) volcano signature; d) E-Nino signature. “*” solar maxima position; the ~0.1K solar cycle signature emerges clearly from the filtering.

Analisi della Temperatura Globale

ACRIM-PMOD controversy: L'irradianza totale del sole e' cresciuta dal 1980 al 2000?

Ricostruzione dell'impronta solare sul clima della superficie

1) τ2 = 12 year and solar [A]

2) τ2 = 8 year and solar [C]

The model well agreeswith this secular temperature reconstruction.The model “predicts” centuries of data!

Scafetta, 2009

τ2 = 12 year and [A]

The model well reconstructsthe decadal cycles of the temperature. (Look at the details)

The sun contributed from 30% to 65% of the observed warming since 1900.

Scafetta, 2009

Ricostruzione dell'impronta solare sul clima della superficie

E' possibile predire il clima? Un forzante astronomicoPresented by Scafetta, at AGU fall meeting 2008; Scafetta 2009

Wobbling of the Sun around the center of mass of the solar system.

The Sun wobbles because of the gravitational attraction of the other planets of the solar system.

In particular because of the Jovian planets:Jupiter, Saturn,Uranus and Neptune.

This generates a tidal force and torque on the sun and on the Earth.

Is this forcing partially shaping solar activityand/or the Earth's climate?

Jose, 1965; Fairbridge and Shirley, 1987; Landscheidt, 1988, 1999; Charvatova and Stvrevstik, 2004; Wilson et al., 2008Hung, 2007

~12 years

~30 years

1) Opposition period : 10 years

2) Jupiter period : 12 years

3) Synodic period : 20 years

4) Saturn period : 30 years

5) Jupiter & Saturn period: 60 years

1) Precesion axis period : 8.85 years

2) Luni-solar nodal period: 18.6 years

VenusEarth

Jupiter

MercuryVenusEarth

Jupiter

Distanza solare e sua velocita' dal centro di massa del sistema solare

95%

Cycle #7 refers mostly to the orbital period of Jupiter, which is 11.86 years; Cycle #9 refers mostly to the synodic period of Jupiter and Saturn, which is about 19.86 years; Cycle #10 refers mostly to the orbital period of Saturn, which is 29.42 years; Cycle #11 is about twice the orbital period of Saturn and five times that of Jupiter and is close to the third higher harmonic of the 178.7 solar cycle periodicity.

Power Spectra Comparison: CLIMATE vs. SCMSS

Ricostruzione dei cicli di 60 e 20 anni usando I cicli solari

[A] Global surface temperature detrended of its quadratic fit plotted against the rescaled 60-year modulation of the velocity of the CMSS: the solar index is lag-shifted by +5 years.

[B] The 20-year oscillation of the climate (grey) plotted against the rescaled velocity (black) of the CMSS detrended of its six decade modulation: no lag-time is applied.

Cicli di 60 anni nelclima

Klyashtorin et al, 2009

Cicli di 60 anni nell'attivita' solare

Ricostruzione della temperatura usando i cicli di 60 e 20 anni del sole

Possibili meccanismi:

a) I movimenti dei pianeti potrebbe modulare l'attivita' solare e questa modula il clima

b) I movimenti dei pianeti modula la lunghezza del giorno e questa modula il clima

Klyashtorin, L.B. (2001) Climate change and long-term fluctuations of commercial catches: the possibility of forecasting.” FAO Fisheries Technical Paper 410. See also: Mazzarella, The Open Atmospheric Science Journal, 2008, 2, 181-184

I cambiamenti climatici e le loro cause: una discussione su alcuni punti chiave

Extraterrestrial influence on the climate

1) Direct solar irradiance forcing The Earth warms when TSI increases and cools when TSI decreases

Cosmic Ray – Ozone-Cloud modulation The Earth is warmed when cosmic ray flux decreases and cooled when cosmic ray flux increases. (This parallel solar activity)

2) Sun-Earth network synchronization The internal modes of Earth synchronize with the extraterrestrial forcings. This yields the climate system to distribute its own internal energy in such a way to “mirror” the patterns of the extraterrestrial forcings.

Current climate models severely underestimate the extraterrestrial effect on climate change because they take into account only the direct TSI forcing.

Measurements of the time constants of the climate systemScafetta, Comment on "Heat capacity, time constant, and sensitivity of Earth's climate system" by S. E. Schwartz, GRL (2008).

Analysis of the autocorrelation of the temperature fluctuation record basedon autoregressive models AR(1)suggests that the climate system is characterized by two relaxation time constants indicating that climateis made of two subsystems with two different heat capacities.

τ1 ~ 0.4 year τ2 ~ 8 or 12 +/- 3 year

error bias analysis

The phenomenological model assumes that the solar signature is made of the superposition of two signals produced by two basic thermodynamic models (TM) with the two found empirical characteristic time constants. (These models are simplified EBMs)

A simplified model with one time constant is discussed in Scafetta and West, JGR 2007.The model herein discussed was presented by Scafetta at the AGU fall meeting 2008.

There is the need of evaluating the scaling factors k1 and k2

TM 1

TM 2

Tinsley et al. (2004)

Did the TSI increase or remain constant after 1980?THE ACRIM - PMOD CONTROVERSY - solved

Nicola Scafetta and Richard Willson, “ACRIM-gap and Total Solar Irradiance (TSI) trend issue resolvedusing a surface magnetic flux TSI proxy model”, in press Geophysical Research Letter (2009) .